Merge pull request #47 from ismagom/master

Fixed problems with PDSCH UE example and synchronization.

cmake/modules/FindVolk.cmake

@@ -42,14 +42,22 @@ CHECK_FUNCTION_EXISTS_MATH(volk_32f_x2_dot_prod_32f HAVE_VOLK_DOTPROD_F_FUNCTION
 CHECK_FUNCTION_EXISTS_MATH(volk_32fc_s32f_atan2_32f HAVE_VOLK_ATAN_FUNCTION)
 CHECK_FUNCTION_EXISTS_MATH(volk_32f_s32f_convert_16i HAVE_VOLK_CONVERT_FI_FUNCTION)
 CHECK_FUNCTION_EXISTS_MATH(volk_32fc_deinterleave_32f_x2 HAVE_VOLK_DEINTERLEAVE_FUNCTION)
-
 CHECK_FUNCTION_EXISTS_MATH(volk_32f_x2_subtract_32f HAVE_VOLK_SUB_FLOAT_FUNCTION)
+CHECK_FUNCTION_EXISTS_MATH(volk_32fc_deinterleave_real_32f HAVE_VOLK_DEINTERLEAVE_FUNCTION)
+CHECK_FUNCTION_EXISTS_MATH(volk_32fc_index_max_16u HAVE_VOLK_MAX_ABS_FUNCTION)
+
 
 
 SET(VOLK_DEFINITIONS "HAVE_VOLK")
+IF(${HAVE_VOLK_MAX_ABS_FUNCTION})
+  SET(VOLK_DEFINITIONS "${VOLK_DEFINITIONS}; HAVE_VOLK_MAX_ABS_FUNCTION")
+ENDIF()
 IF(${HAVE_VOLK_DOTPROD_CONJ_FC_FUNCTION})
   SET(VOLK_DEFINITIONS "${VOLK_DEFINITIONS}; HAVE_VOLK_DOTPROD_CONJ_FC_FUNCTION")
 ENDIF()
+IF(${HAVE_VOLK_DEINTERLEAVE_FUNCTION})
+  SET(VOLK_DEFINITIONS "${VOLK_DEFINITIONS}; HAVE_VOLK_DEINTERLEAVE_FUNCTION")
+ENDIF()
 IF(${HAVE_VOLK_SUB_FLOAT_FUNCTION})
   SET(VOLK_DEFINITIONS "${VOLK_DEFINITIONS}; HAVE_VOLK_SUB_FLOAT_FUNCTION")
 ENDIF()

cuhd/include/liblte/cuhd/cuhd.h

@@ -48,6 +48,8 @@ LIBLTE_API int cuhd_start_rx_stream_nsamples(void *h,
 
 LIBLTE_API int cuhd_stop_rx_stream(void *h);
 
+LIBLTE_API void cuhd_flush_buffer(void *h);
+
 LIBLTE_API bool cuhd_rx_wait_lo_locked(void *h);
 
 LIBLTE_API double cuhd_set_rx_srate(void *h, 

cuhd/lib/cuhd_imp.cpp

@@ -95,6 +95,15 @@ int cuhd_stop_rx_stream(void *h)
   return 0;
 }
 
+void cuhd_flush_buffer(void *h)
+{
+  int n; 
+  _Complex float tmp[1024];
+  do {
+    n = cuhd_recv(h, tmp, 1024, 0);
+  } while (n > 0);  
+}
+
 int cuhd_start_rx_stream_nsamples(void *h, uint32_t nsamples)
 {
   cuhd_handler *handler = static_cast < cuhd_handler * >(h);
@@ -112,6 +121,7 @@ int cuhd_open(char *args, void **h)
   std::string _args = std::string(args);
   handler->usrp = uhd::usrp::multi_usrp::make(_args + ", master_clock_rate=30720000" + ", num_recv_frames=512");
 
+//  handler->usrp = uhd::usrp::multi_usrp::make(_args + ", master_clock_rate=50000000" + ", num_recv_frames=512");
   handler->usrp->set_clock_source("internal");
 
   std::string otw, cpu;

lte/phy/examples/CMakeLists.txt

@@ -51,7 +51,7 @@ LIST(FIND OPTIONAL_LIBS graphics GRAPHICS_FIND)
 # These two can be compiled without UHD or graphics support
 #################################################################
 
-add_executable(pdsch_ue pdsch_ue.c iodev.c)
+add_executable(pdsch_ue pdsch_ue.c iodev.c cell_search_utils.c)
 target_link_libraries(pdsch_ue lte_phy)
 
 add_executable(pdsch_enodeb pdsch_enodeb.c)
@@ -81,8 +81,8 @@ ENDIF(${GRAPHICS_FIND} EQUAL -1)
 
 IF(${CUHD_FIND} GREATER -1)
 
-  add_executable(scan_mib scan_mib.c)
+  add_executable(cell_search cell_search.c cell_search_utils.c)
-  target_link_libraries(scan_mib lte_phy cuhd )
+  target_link_libraries(cell_search lte_phy cuhd )
 
   MESSAGE(STATUS "   UHD examples will be installed.")
 

lte/phy/examples/cell_search.c

@@ -32,10 +32,14 @@
 #include <unistd.h>
 #include <math.h>
 #include <sys/time.h>
+
 #include <unistd.h>
 
 #include "liblte/phy/phy.h"
 
+#include "cell_search_utils.h"
+
+
 #ifndef DISABLE_UHD
 #include "liblte/cuhd/cuhd.h"
 #endif
@@ -45,32 +49,34 @@
 #define FLEN            9600
 #define FLEN_PERIOD     0.005
 
+#define MAX_EARFCN 1000
+
 
 int band = -1;
 int earfcn_start=-1, earfcn_end = -1;
-int nof_frames_find=200;
+int nof_frames_total = 50;
+int nof_frames_detected = 10;
+float threshold = CS_FIND_THRESHOLD; 
 
 
 float uhd_gain = 60.0;
 char *uhd_args=""; 
 
-#define MAX_EARFCN 1000
-lte_earfcn_t channels[MAX_EARFCN];
-
-
 void usage(char *prog) {
-  printf("Usage: %s [asefgv] -b band\n", prog);
+  printf("Usage: %s [agsendtvb] -b band\n", prog);
   printf("\t-a UHD args [Default %s]\n", uhd_args);
   printf("\t-g UHD gain [Default %.2f dB]\n", uhd_gain);
   printf("\t-s earfcn_start [Default All]\n");
   printf("\t-e earfcn_end [Default All]\n");
-  printf("\t-f nof_frames_find [Default %d]\n", nof_frames_find);
+  printf("\t-n nof_frames_total [Default 100]\n");
+  printf("\t-d nof_frames_detected [Default 10]\n");
+  printf("\t-t threshold [Default %.2f]\n",threshold);
   printf("\t-v [set verbose to debug, default none]\n");
 }
 
 void parse_args(int argc, char **argv) {
   int opt;
-  while ((opt = getopt(argc, argv, "asefgvb")) != -1) {
+  while ((opt = getopt(argc, argv, "agsendtvb")) != -1) {
     switch(opt) {
     case 'a':
       uhd_args = argv[optind];
@@ -84,8 +90,14 @@ void parse_args(int argc, char **argv) {
     case 'e':
       earfcn_end = atoi(argv[optind]);
       break;
-    case 'f':
+    case 'n':
-      nof_frames_find = atoi(argv[optind]);
+      nof_frames_total = atoi(argv[optind]);
+      break;
+    case 'd':
+      nof_frames_detected = atoi(argv[optind]);
+      break;
+    case 't':
+      threshold = atof(argv[optind]);
       break;
     case 'g':
       uhd_gain = atof(argv[optind]);
@@ -104,25 +116,16 @@ void parse_args(int argc, char **argv) {
   }
 }
 
-int cuhd_recv_wrapper(void *h, void *data, uint32_t nsamples) {
-  DEBUG(" ----  Receive %d samples  ---- \n", nsamples);
-  return cuhd_recv(h, data, nsamples, 1);
-}
-
-
 int main(int argc, char **argv) {
-  int ret;
+  int n; 
-  int frame_cnt;
-  int nof_freqs; 
-  uint32_t freq;
-  ue_sync_t uesync; 
   void *uhd;
+  ue_celldetect_t s;
+  ue_celldetect_result_t found_cells[3]; 
   cf_t *buffer; 
-  
+  int nof_freqs; 
-  if (argc < 3) {
+  lte_earfcn_t channels[MAX_EARFCN];
-    usage(argv[0]);
+  uint32_t freq;
-    exit(-1);
+  pbch_mib_t mib; 
-  }
 
   parse_args(argc, argv);
     
@@ -131,8 +134,6 @@ int main(int argc, char **argv) {
     fprintf(stderr, "Error opening uhd\n");
     exit(-1);
   }  
- 
-  /* set uhd_gain */
   cuhd_set_rx_gain(uhd, uhd_gain);
   
   nof_freqs = lte_band_get_fd_band(band, channels, earfcn_start, earfcn_end, MAX_EARFCN);
@@ -141,62 +142,62 @@ int main(int argc, char **argv) {
     exit(-1);
   }
     
+  buffer = vec_malloc(sizeof(cf_t) * 96000);
+  if (!buffer) {
+    perror("malloc");
+    return LIBLTE_ERROR;
+  }
   
-  for (freq=0;freq<nof_freqs;freq++) {
+  if (ue_celldetect_init(&s)) {
-    /* set freq */
+    fprintf(stderr, "Error initiating UE sync module\n");
-    cuhd_stop_rx_stream(uhd);
-    cuhd_set_rx_freq(uhd, (double) channels[freq].fd * MHZ);
-    cuhd_rx_wait_lo_locked(uhd);
-        
-    if (ue_sync_init(&uesync, cuhd_set_rx_srate, cuhd_recv_wrapper, uhd)) {
-      fprintf(stderr, "Error initiating UE sync\n");
     exit(-1);
   }
-    ue_sync_set_nof_pbch_decodes(&uesync, 1);
+  if (threshold > 0) {
-    ue_sync_decode_sss_on_track(&uesync, true);
+    ue_celldetect_set_threshold(&s, threshold);    
-    ue_sync_change_srate(&uesync, false);
+  }
   
-    DEBUG("Starting receiver...\n",0);
+  if (nof_frames_total > 0) {
-    cuhd_start_rx_stream(uhd);
+    ue_celldetect_set_nof_frames_total(&s, nof_frames_total);
+  }
+  if (nof_frames_detected > 0) {
+    ue_celldetect_set_nof_frames_detected(&s, nof_frames_detected);
+  }
+
+  for (freq=0;freq<nof_freqs;freq+=10) {
+  
+    /* set uhd_freq */
+    cuhd_set_rx_freq(uhd, (double) channels[freq].fd * MHZ);
+    cuhd_rx_wait_lo_locked(uhd);
     usleep(10000);
+    INFO("Set uhd_freq to %.3f MHz\n", (double) channels[freq].fd * MHZ/1000000);
     
+    printf("[%3d/%d]: EARFCN %d Freq. %.2f MHz looking for PSS. \r", freq, nof_freqs,
+                      channels[freq].id, channels[freq].fd);fflush(stdout);
     
-    /* Receive up to a maximum of nof_frames_find */
+    if (VERBOSE_ISINFO()) {
-    frame_cnt = 0; 
+      printf("\n");
-    ret = 0;
+    }
-    ue_sync_reset(&uesync);
-    agc_reset(&uesync.agc);
     
-    while(frame_cnt < nof_frames_find && ret == 0) {
+    n = find_cell(uhd, &s, buffer, found_cells);
-      ret = ue_sync_get_buffer(&uesync, &buffer);
+    if (n < 0) {
-      if (ret < 0) {
+      fprintf(stderr, "Error searching cell\n");
-        fprintf(stderr, "Error calling ue_sync_work()\n");
       exit(-1);
     }
-      frame_cnt++;
+    if (n == CS_CELL_DETECTED) {
-      printf("[%3d/%d]: EARFCN %d Freq. %.2f MHz looking for PSS. RSSI: %+2.2f dB...\r", freq, nof_freqs,
+      for (int i=0;i<3;i++) {
-                      channels[freq].id, channels[freq].fd, 20*log10f(agc_get_rssi(&uesync.agc)));fflush(stdout);
+        if (found_cells[i].peak > threshold/2) {
-      if (VERBOSE_ISINFO()) {
+          if (decode_pbch(uhd, buffer, &found_cells[i], nof_frames_total, &mib)) {
-        printf("\n");
+            fprintf(stderr, "Error decoding PBCH\n");
+            exit(-1);
           }          
         }
-    if (ret == 1) {
-      if (VERBOSE_ISINFO()) {
-        printf("[%3d/%d]: EARFCN %d Freq. %.2f MHz FOUND MIB ", freq, nof_freqs,
-                    channels[freq].id, channels[freq].fd);
       }
-      printf("RSSI: %+.2f dBm, CFO: %+.4f KHz\n",
-             20*log10f(agc_get_rssi(&uesync.agc)), ue_sync_get_cfo(&uesync));
-      printf("\n");fflush(stdout); 
     }    
-    
-    ue_sync_free(&uesync);      
   }
     
+  ue_celldetect_free(&s);
   cuhd_close(uhd);
-  
-  
-  printf("\n\nDone\n");
   exit(0);
 }
 
+

lte/phy/examples/cell_search_utils.c

@@ -0,0 +1,157 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <math.h>
+#include <sys/time.h>
+
+#include <unistd.h>
+
+#include "liblte/phy/phy.h"
+
+#ifndef DISABLE_UHD
+#include "liblte/cuhd/cuhd.h"
+
+int decode_pbch(void *uhd, cf_t *buffer, ue_celldetect_result_t *found_cell, uint32_t nof_frames_total, pbch_mib_t *mib) 
+{
+  ue_mib_t uemib;
+  int n; 
+  
+  bzero(mib, sizeof(pbch_mib_t));
+  
+  uint32_t nof_frames = 0;
+  uint32_t flen = MIB_FRAME_SIZE;
+  
+  if (ue_mib_init(&uemib, found_cell->cell_id, found_cell->cp)) {
+    fprintf(stderr, "Error initiating PBCH decoder\n");
+    return LIBLTE_ERROR;
+  }
+  
+  INFO("Setting sampling frequency 1.92 MHz for PBCH decoding\n", 0);
+  cuhd_set_rx_srate(uhd, 1920000.0);
+  INFO("Starting receiver...\n", 0);
+  cuhd_start_rx_stream(uhd);
+  
+  do {
+    if (cuhd_recv(uhd, buffer, flen, 1)<0) {
+      fprintf(stderr, "Error receiving from USRP\n");
+      return LIBLTE_ERROR;
+    }      
+    
+    INFO("Calling ue_mib_decode() %d/%d\n", nof_frames, nof_frames_total);
+    
+    n = ue_mib_decode(&uemib, buffer, flen, mib);
+    if (n == LIBLTE_ERROR || n == LIBLTE_ERROR_INVALID_INPUTS) {
+      fprintf(stderr, "Error calling ue_mib_decode()\n");
+      return LIBLTE_ERROR;
+    }
+    if (n == MIB_FRAME_UNALIGNED) {
+      printf("Realigning frame\n");
+      if (cuhd_recv(uhd, buffer, flen/2, 1)<0) {
+        fprintf(stderr, "Error receiving from USRP\n");
+        return LIBLTE_ERROR;
+      }
+    }
+    nof_frames++;
+  } while (n != MIB_FOUND && nof_frames < 2*nof_frames_total);
+  if (n == MIB_FOUND) {
+    printf("\n\nMIB decoded in %d ms (%d half frames)\n", nof_frames*5, nof_frames);
+    pbch_mib_fprint(stdout, mib, found_cell->cell_id);
+  } else {
+    printf("\nCould not decode MIB\n");
+  }
+
+  cuhd_stop_rx_stream(uhd); 
+  cuhd_flush_buffer(uhd);
+
+  ue_mib_free(&uemib);
+  
+  return LIBLTE_SUCCESS; 
+}
+
+int find_cell(void *uhd, ue_celldetect_t *s, cf_t *buffer, ue_celldetect_result_t found_cell[3]) 
+{  
+  int n; 
+
+  INFO("Setting sampling frequency 960 KHz for PSS search\n", 0);
+  cuhd_set_rx_srate(uhd, 960000.0);
+  INFO("Starting receiver...\n", 0);
+  cuhd_start_rx_stream(uhd);
+
+  uint32_t nof_scanned_cells = 0; 
+  uint32_t flen = 4800; 
+  int nof_detected_cells = 0; 
+  
+  do {
+    
+    if (cuhd_recv(uhd, buffer, flen, 1)<0) {
+      fprintf(stderr, "Error receiving from USRP\n");
+      return LIBLTE_ERROR;
+    }
+    
+    n = ue_celldetect_scan(s, buffer, flen, &found_cell[nof_scanned_cells]);
+    switch(n) {
+      case CS_FRAME_UNALIGNED:
+        printf("Realigning frame\n");
+        if (cuhd_recv(uhd, buffer, flen/2, 1)<0) {
+          fprintf(stderr, "Error receiving from USRP\n");
+          return LIBLTE_ERROR;
+        }
+        return LIBLTE_ERROR; 
+      case CS_CELL_DETECTED:
+        nof_detected_cells++;
+        if (found_cell[nof_scanned_cells].peak > 0) {
+          printf("\n\tCELL ID: %d, CP: %s, Peak: %.2f, Mode: %d/%d\n", 
+                found_cell[nof_scanned_cells].cell_id, 
+                lte_cp_string(found_cell[nof_scanned_cells].cp), 
+                found_cell[nof_scanned_cells].peak, found_cell[nof_scanned_cells].mode, 
+                s->nof_frames_detected);                      
+        }
+        
+        nof_scanned_cells++;
+        break;
+      case CS_CELL_NOT_DETECTED:
+        nof_scanned_cells++;
+        break;
+      case LIBLTE_ERROR:
+      case LIBLTE_ERROR_INVALID_INPUTS: 
+        fprintf(stderr, "Error calling cellsearch_scan()\n");
+        return LIBLTE_ERROR;         
+    }
+  } while(nof_scanned_cells < 3);
+
+  INFO("Stopping receiver...\n", 0);
+  cuhd_stop_rx_stream(uhd); 
+  cuhd_flush_buffer(uhd);
+  
+  return nof_detected_cells; 
+}
+#endif

lte/phy/examples/cell_search_utils.h

@@ -0,0 +1,40 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+
+#include "liblte/phy/phy.h"
+
+int decode_pbch(void *uhd, 
+                cf_t *buffer, 
+                ue_celldetect_result_t *found_cell, 
+                uint32_t nof_frames_total, 
+                pbch_mib_t *mib);
+
+int find_cell(void *uhd, 
+              ue_celldetect_t *s, 
+              cf_t *buffer, 
+              ue_celldetect_result_t found_cell[3]);

lte/phy/examples/iodev.c

@@ -29,11 +29,12 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "iodev.h"
 
 #include "liblte/phy/io/filesource.h"
-#include "liblte/phy/phch/ue_sync.h"
+#include "liblte/phy/ue/ue_sync.h"
 #include "liblte/phy/utils/debug.h"
 #include "liblte/phy/utils/vector.h"
 
@@ -41,6 +42,8 @@
 #include "liblte/cuhd/cuhd.h"
 #endif
 
+#include "cell_search_utils.h"
+
 
 int cuhd_recv_wrapper(void *h, void *data, uint32_t nsamples) {
   DEBUG(" ----  Receive %d samples  ---- \n", nsamples);
@@ -48,20 +51,36 @@ int cuhd_recv_wrapper(void *h, void *data, uint32_t nsamples) {
 }
 
 /* Setup USRP or input file */
-int iodev_init(iodev_t *q, iodev_cfg_t *config) {
+int iodev_init(iodev_t *q, iodev_cfg_t *config, lte_cell_t *cell, pbch_mib_t *mib) {
   
   if (config->input_file_name) {
+    
+    mib->phich_resources = R_1; 
+    mib->phich_length = PHICH_NORM;
+    
+    cell->id = config->cell_id_file;
+    cell->cp = CPNORM; 
+    cell->nof_ports = config->nof_ports_file; 
+    cell->nof_prb = config->nof_prb_file; 
+
     if (filesource_init(&q->fsrc, config->input_file_name, COMPLEX_FLOAT_BIN)) {
       return LIBLTE_ERROR;
     }
-    q->input_buffer_file = vec_malloc(SF_LEN_MAX * sizeof(cf_t));
+    q->mode = FILESOURCE;
+    int symbol_sz = lte_symbol_sz(cell->nof_prb);
+    if (symbol_sz > 0) {
+      q->sf_len = SF_LEN(symbol_sz);      
+    } else {
+      fprintf(stderr, "Invalid number of PRB %d\n", cell->nof_prb);
+      return LIBLTE_ERROR; 
+    }
+
+    q->input_buffer_file = vec_malloc(q->sf_len * sizeof(cf_t));
     if (!q->input_buffer_file) {
       perror("malloc");
       return LIBLTE_ERROR; 
     }
-
+    q->sf_idx = 9; 
-    q->mode = FILESOURCE;
-    q->sf_len = 1920;
     
   } else {
 #ifndef DISABLE_UHD
@@ -71,17 +90,76 @@ int iodev_init(iodev_t *q, iodev_cfg_t *config) {
       return LIBLTE_ERROR;
     }
     
-    /* set uhd_freq */
     cuhd_set_rx_gain(q->uhd, config->uhd_gain);
+
+    /* set receiver frequency */
     cuhd_set_rx_freq(q->uhd, (double) config->uhd_freq);
 
     cuhd_rx_wait_lo_locked(q->uhd);
     DEBUG("Set uhd_freq to %.3f MHz\n", (double ) config->uhd_freq);
 
+    int n; 
+    ue_celldetect_t cd;
+    ue_celldetect_result_t found_cells[3];
+
+    cf_t *buffer = vec_malloc(sizeof(cf_t) * 96000);
+    if (!buffer) {
+      perror("malloc");
+      return LIBLTE_ERROR;
+    }
+    if (ue_celldetect_init(&cd)) {
+      fprintf(stderr, "Error initiating UE cell detect\n");
+      exit(-1);
+    }
+    n = find_cell(q->uhd, &cd, buffer, found_cells);
+    if (n < 0) {
+      fprintf(stderr, "Error searching cell\n");
+      exit(-1);
+    }
+
+    int max_peak_cell = 0;
+    float max_peak_value = -1.0;
+    if (n > 0) {
+      for (int i=0;i<3;i++) {
+        if (found_cells[i].peak > max_peak_value) {
+          max_peak_value = found_cells[i].peak;
+          max_peak_cell = i;
+        }
+      }
+      if (decode_pbch(q->uhd, buffer, &found_cells[max_peak_cell], 400, mib)) {
+        fprintf(stderr, "Could not decode PBCH from CELL ID %d\n", found_cells[max_peak_cell].cell_id);
+        return LIBLTE_ERROR;
+      }
+    } else {
+      fprintf(stderr, "Could not find any cell in this frequency\n");
+      return LIBLTE_ERROR;
+    }
+    
+    free(buffer);
+    cell->cp = found_cells[max_peak_cell].cp;
+    cell->id = found_cells[max_peak_cell].cell_id;
+    cell->nof_prb = mib->nof_prb;
+    cell->nof_ports = mib->nof_ports; 
+    
+    /* set sampling frequency */
+    int srate = lte_sampling_freq_hz(cell->nof_prb);
+    if (srate != -1) {  
+      cuhd_set_rx_srate(q->uhd, (double) srate);      
+    } else {
+      fprintf(stderr, "Invalid number of PRB %d\n", cell->nof_prb);
+      return LIBLTE_ERROR;
+    }
+
     DEBUG("Starting receiver...\n", 0);
     cuhd_start_rx_stream(q->uhd);
     
-    ue_sync_init(&q->sframe, cuhd_set_rx_srate, cuhd_recv_wrapper, q->uhd);
+    if (ue_sync_init(&q->sframe, *cell, cuhd_recv_wrapper, q->uhd)) {
+      fprintf(stderr, "Error initiating ue_sync\n");
+      return LIBLTE_ERROR; 
+    }
+
+    /* Decodes the SSS signal during the tracking phase. Extra overhead, but makes sure we are in the correct subframe */  
+    ue_sync_decode_sss_on_track(&q->sframe, true);
 
     // Here, the subframe length and input buffer is managed by ue_sync
     q->mode = UHD; 
@@ -113,7 +191,7 @@ void iodev_free(iodev_t *q) {
 int iodev_receive(iodev_t *q, cf_t **buffer) {
   int n; 
   if (q->mode == FILESOURCE) {
-    DEBUG(" -----   READING %d SAMPLES ---- \n", q->sf_len);
+    INFO(" -----   READING %d SAMPLES ---- \n", q->sf_len);
     n = filesource_read(&q->fsrc, q->input_buffer_file, q->sf_len);
     *buffer = q->input_buffer_file; 
     if (n == -1) {
@@ -132,6 +210,11 @@ int iodev_receive(iodev_t *q, cf_t **buffer) {
     } else {
       n = 1; 
     }
+    q->sf_idx++;
+    if (q->sf_idx == 10) {
+      q->sf_idx = 0;
+    }
+    usleep(5000);
   } else {
     /* Use ue_sync_work which returns a synchronized buffer of subframe samples */
 #ifndef DISABLE_UHD
@@ -160,4 +243,12 @@ bool iodev_isUSRP(iodev_t *q) {
   return q->mode == UHD;
 }
 
+uint32_t iodev_get_sfidx(iodev_t *q) {
+  if (iodev_isfile(q)) {
+    return q->sf_idx;
+  } else {
+    return ue_sync_get_sfidx(&q->sframe);
+  }
+}
+
 

lte/phy/examples/iodev.h

@@ -30,7 +30,7 @@
 
 #include "liblte/config.h"
 
-#include "liblte/phy/phch/ue_sync.h"
+#include "liblte/phy/ue/ue_sync.h"
 #include "liblte/phy/io/filesource.h"
 
 #ifndef DISABLE_UHD
@@ -54,6 +54,10 @@ typedef _Complex float cf_t;
 
 typedef struct LIBLTE_API {
   char *input_file_name;
+  uint32_t cell_id_file;
+  uint32_t nof_prb_file;
+  uint32_t nof_ports_file; 
+
   float uhd_freq;
   float uhd_gain;
   char *uhd_args;
@@ -66,6 +70,7 @@ typedef struct LIBLTE_API {
   ue_sync_t sframe;
   #endif
   uint32_t sf_len; 
+  uint32_t sf_idx;
   cf_t *input_buffer_file; // for UHD mode, the input buffer is managed by sync_frame_t
   filesource_t fsrc;  
   iodev_cfg_t config; 
@@ -74,7 +79,9 @@ typedef struct LIBLTE_API {
 
 
 LIBLTE_API int iodev_init(iodev_t *q, 
-                          iodev_cfg_t *config);
+                          iodev_cfg_t *config, 
+                          lte_cell_t *cell, 
+                          pbch_mib_t *mib);
 
 LIBLTE_API void iodev_free(iodev_t *q);
 
@@ -83,6 +90,8 @@ LIBLTE_API int iodev_receive(iodev_t *q,
 
 LIBLTE_API void* iodev_get_cuhd(iodev_t *q);
 
+LIBLTE_API uint32_t iodev_get_sfidx(iodev_t *q);
+
 LIBLTE_API bool iodev_isfile(iodev_t *q); 
 
 LIBLTE_API bool iodev_isUSRP(iodev_t *q); 

lte/phy/examples/pdsch_enodeb.c

@@ -52,7 +52,7 @@ uint32_t mcs_idx = 12;
 int nof_frames = -1;
 
 char *uhd_args = "";
-float uhd_amp = 0.25, uhd_gain = 10.0, uhd_freq = 2400000000;
+float uhd_amp = 0.01, uhd_gain = 10.0, uhd_freq = 2400000000;
 
 filesink_t fsink;
 lte_fft_t ifft;
@@ -70,6 +70,7 @@ void usage(char *prog) {
   printf("Usage: %s [agmfoncvp]\n", prog);
 #ifndef DISABLE_UHD
   printf("\t-a UHD args [Default %s]\n", uhd_args);
+  printf("\t-l UHD amplitude [Default %.2f]\n", uhd_amp);
   printf("\t-g UHD TX gain [Default %.2f dB]\n", uhd_gain);
   printf("\t-f UHD TX frequency [Default %.1f MHz]\n", uhd_freq / 1000000);
 #else
@@ -85,7 +86,7 @@ void usage(char *prog) {
 
 void parse_args(int argc, char **argv) {
   int opt;
-  while ((opt = getopt(argc, argv, "agfmoncpv")) != -1) {
+  while ((opt = getopt(argc, argv, "aglfmoncpv")) != -1) {
     switch (opt) {
     case 'a':
       uhd_args = argv[optind];
@@ -93,6 +94,9 @@ void parse_args(int argc, char **argv) {
     case 'g':
       uhd_gain = atof(argv[optind]);
       break;
+    case 'l':
+      uhd_amp = atof(argv[optind]);
+      break;
     case 'f':
       uhd_freq = atof(argv[optind]);
       break;
@@ -253,7 +257,7 @@ int main(int argc, char **argv) {
 
   N_id_2 = cell.id % 3;
   sf_n_re = 2 * CPNORM_NSYMB * cell.nof_prb * RE_X_RB;
-  sf_n_samples = 2 * SLOT_LEN_CPNORM(lte_symbol_sz(cell.nof_prb));
+  sf_n_samples = 2 * SLOT_LEN(lte_symbol_sz(cell.nof_prb));
 
   /* this *must* be called after setting slot_len_* */
   base_init();
@@ -355,7 +359,10 @@ int main(int argc, char **argv) {
         exit(-1);
       }
       
-      pdsch_encode(&pdsch, data, sf_symbols, sf_idx, &harq_process, ra_dl.rv_idx);        
+      if (pdsch_encode(&pdsch, data, sf_symbols, sf_idx, &harq_process, ra_dl.rv_idx)) {
+        fprintf(stderr, "Error encoding PDSCH\n");
+        exit(-1);
+      }
 
       /* Transform to OFDM symbols */
       lte_ifft_run_sf(&ifft, sf_buffer, output_buffer);

lte/phy/examples/pdsch_ue.c

@@ -53,8 +53,6 @@ void init_plots();
  *  Program arguments processing
  ***********************************************************************/
 typedef struct {
-  uint32_t cell_id_file;
-  uint32_t nof_prb_file; 
   uint16_t rnti; 
   int nof_subframes;
   bool disable_plots;
@@ -62,8 +60,9 @@ typedef struct {
 }prog_args_t;
 
 void args_default(prog_args_t *args) {
-  args->cell_id_file = 1; 
+  args->io_config.cell_id_file = 195; 
-  args->nof_prb_file = 6;
+  args->io_config.nof_prb_file = 50;
+  args->io_config.nof_ports_file = 2; 
   args->rnti = SIRNTI;
   args->nof_subframes = -1; 
   args->disable_plots = false; 
@@ -71,13 +70,14 @@ void args_default(prog_args_t *args) {
   args->io_config.input_file_name = NULL; 
   args->io_config.uhd_args = "";
   args->io_config.uhd_freq = -1.0;
-  args->io_config.uhd_gain = 20.0; 
+  args->io_config.uhd_gain = 60.0; 
 }
 
 void usage(prog_args_t *args, char *prog) {
   printf("Usage: %s [cargfndvtb] [-i input_file | -f rx_frequency (in Hz)]\n", prog);
-  printf("\t-c cell_id if reading from file [Default %d]\n", args->cell_id_file);
+  printf("\t-c cell_id if reading from file [Default %d]\n", args->io_config.cell_id_file);
-  printf("\t-p nof_prb if reading from file [Default %d]\n", args->nof_prb_file);
+  printf("\t-p nof_prb if reading from file [Default %d]\n", args->io_config.nof_prb_file);
+  printf("\t-o nof_ports if reading from file [Default %d]\n", args->io_config.nof_ports_file);
   printf("\t-r RNTI to look for [Default 0x%x]\n", args->rnti);
 #ifndef DISABLE_UHD
   printf("\t-a UHD args [Default %s]\n", args->io_config.uhd_args);
@@ -99,16 +99,19 @@ void usage(prog_args_t *args, char *prog) {
 void parse_args(prog_args_t *args, int argc, char **argv) {
   int opt;
   args_default(args);
-  while ((opt = getopt(argc, argv, "icagfndvtbp")) != -1) {
+  while ((opt = getopt(argc, argv, "icagfndvtbpro")) != -1) {
     switch (opt) {
     case 'i':
       args->io_config.input_file_name = argv[optind];
       break;
     case 'c':
-      args->cell_id_file = atoi(argv[optind]);
+      args->io_config.cell_id_file = atoi(argv[optind]);
       break;
     case 'p':
-      args->nof_prb_file = atoi(argv[optind]);
+      args->io_config.nof_prb_file = atoi(argv[optind]);
+      break;
+    case 'o':
+      args->io_config.nof_ports_file = atoi(argv[optind]);
       break;
     case 'a':
       args->io_config.uhd_args = argv[optind];
@@ -125,6 +128,9 @@ void parse_args(prog_args_t *args, int argc, char **argv) {
     case 'n':
       args->nof_subframes = atoi(argv[optind]);
       break;
+    case 'r':
+      args->rnti= atoi(argv[optind]);
+      break;
     case 'd':
       args->disable_plots = true;
       break;
@@ -149,6 +155,8 @@ void sigintHandler(int x) {
 /* TODO: Do something with the output data */
 char data[10000];
 
+extern float mean_exec_time; 
+
 int main(int argc, char **argv) {
   int ret; 
   cf_t *sf_buffer; 
@@ -156,20 +164,13 @@ int main(int argc, char **argv) {
   prog_args_t prog_args; 
   lte_cell_t cell; 
   ue_dl_t ue_dl; 
-  bool ue_dl_initiated = false; 
   int64_t sf_cnt;
-  uint32_t sf_idx;
   pbch_mib_t mib; 
   bool printed_sib = false; 
   int rlen; 
   
   parse_args(&prog_args, argc, argv);
   
-  if (iodev_init(&iodev, &prog_args.io_config)) {
-    fprintf(stderr, "Error initiating input device\n");
-    exit(-1);
-  }
-  
 #ifndef DISABLE_GRAPHICS
   if (!prog_args.disable_plots) {
     init_plots();    
@@ -180,15 +181,18 @@ int main(int argc, char **argv) {
   printf("\n --- Press Ctrl+C to exit --- \n");
   signal(SIGINT, sigintHandler);
 
-  /* Initialize frame and subframe counters */
+  /* Initialize subframe counter */
   sf_cnt = 0;
-  sf_idx = 0; 
 
-  /* Decodes the SSS signal during the tracking phase. Extra overhead, but makes sure we are in the correct subframe */  
+  if (iodev_init(&iodev, &prog_args.io_config, &cell, &mib)) {
-  ue_sync_decode_sss_on_track(&iodev.sframe, true);
+    exit(-1);
+  }
 
-  /* Decodes the PBCH on each frame. Around 10% more overhead, but makes sure we are in the current System Frame Number (SFN) */
+  if (ue_dl_init(&ue_dl, cell, mib.phich_resources, mib.phich_length, 1234)) { 
-  ue_sync_pbch_always(&iodev.sframe, false);
+    fprintf(stderr, "Error initiating UE downlink processing module\n");
+    exit(-1);
+  }
+  pdsch_set_rnti(&ue_dl.pdsch, prog_args.rnti);
   
   /* Main loop */
   while (!go_exit && (sf_cnt < prog_args.nof_subframes || prog_args.nof_subframes == -1)) {
@@ -200,33 +204,8 @@ int main(int argc, char **argv) {
     }
     
     /* iodev_receive returns 1 if successfully read 1 aligned subframe */
-    if (ret == 0) {
+    if (ret == 1) {
-    printf("Finding PSS... Peak: %8.1f, Output level: %+.2f dB\r", 
+      rlen = ue_dl_decode(&ue_dl, sf_buffer, data, iodev_get_sfidx(&iodev), prog_args.rnti);
-             sync_get_peak_value(&iodev.sframe.s), 10*log10f(agc_get_gain(&iodev.sframe.agc)));      
-    } else if (ret == 1) {
-      if (!ue_dl_initiated) {
-        if (iodev_isUSRP(&iodev)) {
-          cell = ue_sync_get_cell(&iodev.sframe);
-          mib = ue_sync_get_mib(&iodev.sframe);
-        } else {
-          cell.id = prog_args.cell_id_file;
-          cell.cp = CPNORM; 
-          cell.nof_ports = 1; // TODO: Use prog_args 
-          cell.nof_prb = prog_args.nof_prb_file; 
-          mib.phich_resources = R_1; 
-          mib.phich_length = PHICH_NORM;
-        }        
-        if (ue_dl_init(&ue_dl, cell, mib.phich_resources, mib.phich_length, 1234)) { 
-          fprintf(stderr, "Error initiating UE downlink processing module\n");
-          exit(-1);
-        }
-        pdsch_set_rnti(&ue_dl.pdsch, prog_args.rnti);
-        ue_dl_initiated = true; 
-      } else {
-        if (iodev_isUSRP(&iodev)) {
-          sf_idx = ue_sync_get_sfidx(&iodev.sframe);
-        } 
-        rlen = ue_dl_receive(&ue_dl, sf_buffer, data, sf_idx, ue_sync_get_mib(&iodev.sframe).sfn, prog_args.rnti);
       if (rlen < 0) {
         fprintf(stderr, "\nError running receiver\n");fflush(stdout);
         exit(-1);
@@ -237,42 +216,29 @@ int main(int argc, char **argv) {
         printf("\n");fflush(stdout);
         printed_sib = true; 
       }
+
+      // Plot and Printf
       if (!(sf_cnt % 10)) {       
-          printf("RSSI: %+.2f dBm, CFO: %+.4f KHz, SFO: %+.4f Khz, TimeOffset: %4d, Errors: %4d/%4d, BLER: %.1e\r",
+        printf("CFO: %+.4f KHz, SFO: %+.4f Khz, NOI: %.2f Errors: %4d/%4d, BLER: %.1e, Texec: %.2f\r",
-                 20*log10f(agc_get_rssi(&iodev.sframe.agc))+30, 
+                ue_sync_get_cfo(&iodev.sframe)/1000, ue_sync_get_sfo(&iodev.sframe)/1000, 
-                 ue_sync_get_cfo(&iodev.sframe)/1000, ue_sync_get_sfo(&iodev.sframe)/1000, iodev.sframe.peak_idx,
+                pdsch_average_noi(&ue_dl.pdsch),
-                 (int) ue_dl.pkt_errors, (int) ue_dl.pkts_total, (float) ue_dl.pkt_errors / ue_dl.pkts_total);
+                (int) ue_dl.pkt_errors, (int) ue_dl.pkts_total, (float) ue_dl.pkt_errors / ue_dl.pkts_total, 
-          
+               mean_exec_time);                
-          fflush(stdout);       
-          if (VERBOSE_ISINFO()) {
-            printf("\n");
-          }
       }      
       #ifndef DISABLE_GRAPHICS
-        if (!prog_args.disable_plots && sf_idx == 5) {
+      if (!prog_args.disable_plots && iodev_get_sfidx(&iodev) == 5) {
-          do_plots(&ue_dl, sf_idx);          
+        do_plots(&ue_dl, 5);          
       }
       #endif
+    } else if (ret == 0) {
+      printf("Finding PSS... Peak: %8.1f, FrameCnt: %d, State: %d\r", 
+        sync_get_peak_value(&iodev.sframe.sfind), 
+        iodev.sframe.frame_total_cnt, iodev.sframe.state);      
     }
-      if (iodev_isfile(&iodev)) {
-        sf_idx++;       
-        if (sf_idx == NSUBFRAMES_X_FRAME) {
-          sf_idx = 0;
-        }        
-      }
-    }
-
-    if (prog_args.nof_subframes > 0) {
     sf_cnt++;                  
-    }    
+  } // Main loop
-    if (iodev_isfile(&iodev)) {
-      usleep(5000);
-    }
-  }
 
-  if (ue_dl_initiated) {
   ue_dl_free(&ue_dl);    
-  }
   iodev_free(&iodev);
 
   printf("\nBye\n");

lte/phy/examples/synch_file.c

@@ -109,7 +109,6 @@ int main(int argc, char **argv) {
   int peak_pos[3];
   float *cfo;
   float peak_value[3];
-  float mean_value[3];
   int frame_cnt;
   cf_t *input;
   uint32_t m0, m1;
@@ -201,10 +200,10 @@ int main(int argc, char **argv) {
 
     if (force_N_id_2 != -1) {
       N_id_2 = force_N_id_2;
-      peak_pos[N_id_2] = pss_synch_find_pss(&pss[N_id_2], input, &peak_value[N_id_2], &mean_value[N_id_2]);
+      peak_pos[N_id_2] = pss_synch_find_pss(&pss[N_id_2], input, &peak_value[N_id_2]);
     } else {
       for (N_id_2=0;N_id_2<3;N_id_2++) {
-        peak_pos[N_id_2] = pss_synch_find_pss(&pss[N_id_2], input, &peak_value[N_id_2], &mean_value[N_id_2]);
+        peak_pos[N_id_2] = pss_synch_find_pss(&pss[N_id_2], input, &peak_value[N_id_2]);
       }
       float max_value=-99999;
       N_id_2=-1;
@@ -218,7 +217,7 @@ int main(int argc, char **argv) {
     }
 
     /* If peak detected */
-    if (peak_value[N_id_2]/mean_value[N_id_2] > corr_peak_threshold) {
+    if (peak_value[N_id_2] > corr_peak_threshold) {
 
       sss_idx = peak_pos[N_id_2]-2*(symbol_sz+CP(symbol_sz,CPNORM_LEN));
       if (sss_idx >= 0) {
@@ -228,7 +227,7 @@ int main(int argc, char **argv) {
         cfo[frame_cnt] = pss_synch_cfo_compute(&pss[N_id_2], &input[peak_pos[N_id_2]-128]);
         printf("\t%d\t%d\t%d\t%d\t%.3f\t\t%3d\t%d\t%d\t%.3f\n",
             frame_cnt,N_id_2, sss_synch_N_id_1(&sss[N_id_2], m0, m1),
-            sss_synch_subframe(m0, m1), peak_value[N_id_2]/mean_value[N_id_2],
+            sss_synch_subframe(m0, m1), peak_value[N_id_2],
             peak_pos[N_id_2], m0, m1,
             cfo[frame_cnt]);
       }

lte/phy/include/liblte/phy/channel/ch_awgn.h

@@ -27,6 +27,8 @@
 
 
 #include <complex.h>
+#include <stdint.h>
+
 #include "liblte/config.h"
 
 #ifndef CH_AWGN_
@@ -37,13 +39,15 @@ typedef _Complex float cf_t;
 LIBLTE_API void ch_awgn_c(const cf_t* input, 
                           cf_t* output, 
                           float variance, 
-                          int buff_sz);
+                          uint32_t len);
 
 LIBLTE_API void ch_awgn_f(const float* x, 
                           float* y, 
                           float variance, 
-                          int buff_sz);
+                          uint32_t len);
 
+LIBLTE_API float ch_awgn_get_variance(float ebno_db, 
+                                      float rate);
 
 /* High-level API */
 

lte/phy/include/liblte/phy/common/phy_common.h

@@ -65,12 +65,12 @@ typedef enum {CPNORM, CPEXT} lte_cp_t;
 #define SYMBOL_SZ_MAX   2048
 
 #define CPNORM_NSYMB    7
-#define CPNORM_SF_NSYMB 2*CPNORM_NSYMB
+#define CPNORM_SF_NSYMB (2*CPNORM_NSYMB)
 #define CPNORM_0_LEN    160
 #define CPNORM_LEN      144
 
 #define CPEXT_NSYMB     6
-#define CPEXT_SF_NSYMB  2*CPEXT_NSYMB
+#define CPEXT_SF_NSYMB  (2*CPEXT_NSYMB)
 #define CPEXT_LEN       512
 #define CPEXT_7_5_LEN   1024
 
@@ -78,18 +78,13 @@ typedef enum {CPNORM, CPEXT} lte_cp_t;
 #define CP_ISEXT(cp) (cp==CPEXT)
 #define CP_NSYMB(cp) (CP_ISNORM(cp)?CPNORM_NSYMB:CPEXT_NSYMB)
 
-#define CP(symbol_sz, c) (c*symbol_sz/2048)
+#define CP(symbol_sz, c) ((c*symbol_sz)/2048)
-#define CP_NORM(symbol, symbol_sz) (symbol==0)?CP(symbol_sz,CPNORM_0_LEN):CP(symbol_sz,CPNORM_LEN)
+#define CP_NORM(symbol, symbol_sz) ((symbol==0)?CP((symbol_sz),CPNORM_0_LEN):CP((symbol_sz),CPNORM_LEN))
-#define CP_EXT(symbol_sz) CP(symbol_sz,CPEXT_LEN)
+#define CP_EXT(symbol_sz) (CP((symbol_sz),CPEXT_LEN))
 
-#define SLOT_LEN_CPNORM(symbol_sz) (symbol_sz+CP(symbol_sz,CPNORM_0_LEN)+(CPNORM_NSYMB-1)*(symbol_sz+CP(symbol_sz,CPNORM_LEN)))
+#define SLOT_LEN(symbol_sz)     (480*((symbol_sz)/64))
-#define SLOT_LEN_CPEXT(symbol_sz) (CPEXT_NSYMB*(symbol_sz+CP(symbol_sz, CPEXT_LEN)))
+#define SF_LEN(symbol_sz)       (2*SLOT_LEN(symbol_sz))
-#define SLOT_LEN(symbol_sz, cp) (CP_ISNORM(cp)?SLOT_LEN_CPNORM(symbol_sz):SLOT_LEN_CPEXT(symbol_sz))
+#define SF_LEN_MAX              (SF_LEN(SYMBOL_SZ_MAX))
-
-#define SF_LEN_CPNORM(symbol_sz) (2*SLOT_LEN_CPNORM(symbol_sz))
-#define SF_LEN_CPEXT(symbol_sz) (2*SLOT_LEN_CPEXT(symbol_sz))
-#define SF_LEN(symbol_sz, cp) (2*SLOT_LEN(symbol_sz, cp))
-#define SF_LEN_MAX      SF_LEN(SYMBOL_SZ_MAX, CPNORM)
 
 #define SLOT_LEN_RE(nof_prb, cp)        (nof_prb*RE_X_RB*CP_NSYMB(cp))
 #define SF_LEN_RE(nof_prb, cp)          (2*SLOT_LEN_RE(nof_prb, cp))

lte/phy/include/liblte/phy/phch/pbch.h

@@ -89,13 +89,13 @@ LIBLTE_API int pbch_init(pbch_t *q,
 
 LIBLTE_API void pbch_free(pbch_t *q);
 LIBLTE_API int pbch_decode(pbch_t *q, 
-                           cf_t *sf_symbols, 
+                           cf_t *slot1_symbols, 
-                           cf_t *ce[MAX_PORTS], 
+                           cf_t *ce_slot1[MAX_PORTS], 
                            pbch_mib_t *mib);
 
 LIBLTE_API int pbch_encode(pbch_t *q, 
                             pbch_mib_t *mib, 
-                            cf_t *sf_symbols[MAX_PORTS]);
+                            cf_t *slot1_symbols[MAX_PORTS]);
 
 LIBLTE_API void pbch_decode_reset(pbch_t *q);
 

lte/phy/include/liblte/phy/phch/pdsch.h

@@ -43,7 +43,7 @@
 #include "liblte/phy/phch/dci.h"
 #include "liblte/phy/phch/regs.h"
 
-#define TDEC_ITERATIONS         6
+#define TDEC_MAX_ITERATIONS         6
 
 typedef _Complex float cf_t;
 
@@ -75,6 +75,9 @@ typedef struct LIBLTE_API {
   uint32_t max_symbols;
   bool rnti_is_set; 
   uint16_t rnti; 
+  uint32_t nof_iterations; 
+  uint64_t average_nof_iterations_n; 
+  float average_nof_iterations; 
   
   /* buffers */
   // void buffers are shared for tx and rx
@@ -128,6 +131,10 @@ LIBLTE_API int pdsch_decode(pdsch_t *q,
                             pdsch_harq_t *harq_process, 
                             uint32_t rv_idx);
 
+LIBLTE_API float pdsch_average_noi(pdsch_t *q); 
+
+LIBLTE_API uint32_t pdsch_last_noi(pdsch_t *q); 
+
 LIBLTE_API int pdsch_get(pdsch_t *q, 
                          cf_t *sf_symbols, 
                          cf_t *pdsch_symbols,

lte/phy/include/liblte/phy/phy.h

@@ -92,8 +92,11 @@
 #include "liblte/phy/phch/pbch.h"
 #include "liblte/phy/phch/pcfich.h"
 #include "liblte/phy/phch/phich.h"
-#include "liblte/phy/phch/ue_sync.h"
+      
-#include "liblte/phy/phch/ue_dl.h"
+#include "liblte/phy/ue/ue_sync.h"
+#include "liblte/phy/ue/ue_mib.h"
+#include "liblte/phy/ue/ue_celldetect.h"
+#include "liblte/phy/ue/ue_dl.h"
 
 #include "liblte/phy/scrambling/scrambling.h"
 

lte/phy/include/liblte/phy/sync/pss.h

@@ -72,7 +72,6 @@ typedef struct LIBLTE_API {
 
   cf_t *pss_signal_freq[3]; // One sequence for each N_id_2
   cf_t *tmp_input;
-  float *conv_abs;
   cf_t *conv_output;
     
 }pss_synch_t;
@@ -102,8 +101,7 @@ LIBLTE_API int pss_synch_set_N_id_2(pss_synch_t *q,
 
 LIBLTE_API int pss_synch_find_pss(pss_synch_t *q, 
                                   cf_t *input, 
-                                  float *corr_peak_value, 
+                                  float *corr_peak_value);
-                                  float *corr_mean_value);
 
 LIBLTE_API float pss_synch_cfo_compute(pss_synch_t* q, 
                                        cf_t *pss_recv);

lte/phy/include/liblte/phy/sync/sync.h

@@ -51,75 +51,60 @@
  * functions sync_pss_det_absolute() and sync_pss_det_peakmean().
  */
 
-enum sync_pss_det { ABSOLUTE, PEAK_MEAN};
-
 typedef struct LIBLTE_API {
-  pss_synch_t pss_find; 
+  pss_synch_t pss; 
-  pss_synch_t pss_track; 
   sss_synch_t sss;
-  enum sync_pss_det pss_mode;
+  float threshold;
-  float find_threshold;
+  float mean_energy; 
-  float track_threshold;
   float peak_value;
+  float mean_peak_value;
   uint32_t N_id_2;
   uint32_t N_id_1;
-  uint32_t slot_id;
+  uint32_t sf_idx;
   uint32_t fft_size;
-  uint32_t find_frame_size;
+  uint32_t frame_size;
+  uint64_t frame_cnt; 
   float cfo;
   bool detect_cp;
   bool sss_en;
+  bool normalize_en; 
   lte_cp_t cp;
 }sync_t;
 
 
 LIBLTE_API int sync_init(sync_t *q, 
-                         uint32_t find_frame_size, 
+                         uint32_t frame_size, 
-                         uint32_t track_frame_size,
                          uint32_t fft_size);
 
 LIBLTE_API void sync_free(sync_t *q);
 
-LIBLTE_API int sync_realloc(sync_t *q,
+LIBLTE_API void sync_reset(sync_t *q); 
-                            uint32_t find_frame_size, 
-                            uint32_t track_frame_size,
-                            uint32_t fft_size);
 
-/* Finds a correlation peak in the input signal. The signal must be sampled at 1.92 MHz and should be 
+/* Finds a correlation peak in the input signal around position find_offset */
- subframe_size long at least */
 LIBLTE_API int sync_find(sync_t *q, 
                          cf_t *input,
-                         uint32_t *peak_position);
+                         uint32_t find_offset,
-
-/* Tracks the correlation peak in the input signal. The signal must be sampled at 1.92 MHz and should be 
- TRACK_LEN long at least */
-LIBLTE_API int sync_track(sync_t *q, 
-                          cf_t *input,
-                          uint32_t offset, 
                          uint32_t *peak_position);
 
 /* Sets the threshold for peak comparison */
 LIBLTE_API void sync_set_threshold(sync_t *q, 
-                                   float find_threshold,
+                                   float threshold);
-                                   float track_threshold);
-
-/* Set peak comparison to absolute value */
-LIBLTE_API void sync_pss_det_absolute(sync_t *q);
 
-/* Set peak comparison to relative to the mean */
+/* Gets the subframe idx (0 or 5) */
-LIBLTE_API void sync_pss_det_peak_to_avg(sync_t *q);
+LIBLTE_API uint32_t sync_get_sf_idx(sync_t *q);
 
-/* Gets the slot id (0 or 10) */
+/* Gets the last peak value */
-LIBLTE_API uint32_t sync_get_slot_id(sync_t *q);
+LIBLTE_API float sync_get_last_peak_value(sync_t *q);
 
-/* Gets the last peak-to-average ratio */
+/* Gets the mean peak value */
 LIBLTE_API float sync_get_peak_value(sync_t *q);
 
-/* Gets the N_id_2 from the last call to synch_run() */
+/* Gets the last input signal energy estimation value */
-LIBLTE_API uint32_t sync_get_N_id_2(sync_t *q);
+LIBLTE_API float sync_get_input_energy(sync_t *q);
 
-/* Gets the N_id_1 from the last call to synch_run() */
+/* Sets the N_id_2 to search for */
-LIBLTE_API uint32_t sync_get_N_id_1(sync_t *q);
+LIBLTE_API int sync_set_N_id_2(sync_t *q, 
+                                    uint32_t N_id_2);
 
 /* Gets the Physical CellId from the last call to synch_run() */
 LIBLTE_API int sync_get_cell_id(sync_t *q);
@@ -130,6 +115,10 @@ LIBLTE_API float sync_get_cfo(sync_t *q);
 /* Gets the CP length estimation from the last call to synch_run() */
 LIBLTE_API lte_cp_t sync_get_cp(sync_t *q);
 
+/* Enables/Disables energy normalization every frame. If disabled, uses the mean */
+LIBLTE_API void sync_normalize_en(sync_t *q, 
+                                  bool enable);
+
 /* Enables/Disables SSS detection  */
 LIBLTE_API void sync_sss_en(sync_t *q, 
                             bool enabled);

lte/phy/include/liblte/phy/ue/ue_celldetect.h

@@ -0,0 +1,131 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#ifndef UE_CELLSEARCH_
+#define UE_CELLSEARCH_
+
+#include <stdbool.h>
+
+#include "liblte/config.h"
+#include "liblte/phy/sync/sync.h"
+#include "liblte/phy/sync/cfo.h"
+#include "liblte/phy/ch_estimation/chest.h"
+#include "liblte/phy/phch/pbch.h"
+#include "liblte/phy/common/fft.h"
+
+/************************************************************
+ * 
+ * This object scans a signal for LTE cells using the known PSS 
+ * and SSS sequences. 
+ * 
+ * The function ue_celldetect_scan() shall be called multiple times, 
+ * each passing a number of samples multiple of 4800, sampled at 960 KHz
+ * (that is, 5 ms of samples). 
+ * 
+ * The function returns 0 until a signal is found nof_frames_detected times or 
+ * after nof_frames_total with no signal detected. 
+ * 
+ * See ue_cell_detect.c for an example. 
+ * 
+ ************************************************************/
+
+/** 
+ * TODO: Check also peak offset 
+ */
+
+#define CS_DEFAULT_MAXFRAMES_TOTAL      300
+#define CS_DEFAULT_MAXFRAMES_DETECTED   30
+
+#define CS_DEFAULT_NOFFRAMES_TOTAL      100
+#define CS_DEFAULT_NOFFRAMES_DETECTED   10
+
+#define CS_FIND_THRESHOLD          0.6
+
+#define CS_FRAME_UNALIGNED     -3
+#define CS_CELL_DETECTED        2
+#define CS_CELL_NOT_DETECTED    1
+
+typedef struct LIBLTE_API {
+  uint32_t cell_id; 
+  lte_cp_t cp; 
+  float peak; 
+  uint32_t mode; 
+} ue_celldetect_result_t;
+
+
+typedef struct LIBLTE_API {
+  sync_t sfind;
+  uint32_t max_frames_total;
+  uint32_t max_frames_detected;
+  uint32_t nof_frames_total;
+  uint32_t nof_frames_detected;
+  
+  uint32_t current_nof_detected; 
+  uint32_t current_nof_total; 
+  
+  uint32_t current_N_id_2;
+
+  uint32_t *mode_ntimes;
+  char *mode_counted; 
+  
+  ue_celldetect_result_t *candidates; 
+} ue_celldetect_t;
+
+
+LIBLTE_API int ue_celldetect_init(ue_celldetect_t *q);
+
+LIBLTE_API int ue_celldetect_init_max(ue_celldetect_t *q, 
+                                      uint32_t max_frames_total, 
+                                      uint32_t max_frames_detected);
+
+LIBLTE_API void ue_celldetect_free(ue_celldetect_t *q);
+
+LIBLTE_API void ue_celldetect_reset(ue_celldetect_t *q);
+
+LIBLTE_API int ue_celldetect_scan(ue_celldetect_t *q,
+                                  cf_t *signal, 
+                                  uint32_t nsamples,
+                                  ue_celldetect_result_t *found_cell);
+
+LIBLTE_API int ue_celldetect_set_nof_frames_total(ue_celldetect_t *q, 
+                                                   uint32_t nof_frames);
+
+LIBLTE_API int ue_celldetect_set_nof_frames_detected(ue_celldetect_t *q, 
+                                                      uint32_t nof_frames);
+
+LIBLTE_API void ue_celldetect_set_threshold(ue_celldetect_t *q, 
+                                            float threshold); 
+
+LIBLTE_API void ue_celldetect_reset(ue_celldetect_t *q);
+
+
+
+
+
+
+#endif // SYNC_FRAME_
+

lte/phy/include/liblte/phy/ue/ue_dl.h

@@ -57,6 +57,7 @@
 #define NOF_HARQ_PROCESSES 8
 
 typedef struct LIBLTE_API {
+  pbch_t pbch; 
   pcfich_t pcfich;
   pdcch_t pdcch;
   pdsch_t pdsch;
@@ -74,6 +75,9 @@ typedef struct LIBLTE_API {
   uint64_t pkts_total;
   uint64_t nof_trials;
 
+  uint32_t sfn; 
+  bool pbch_decoded; 
+  
   uint16_t user_rnti; 
 }ue_dl_t;
 
@@ -86,11 +90,10 @@ LIBLTE_API int ue_dl_init(ue_dl_t *q,
 
 LIBLTE_API void ue_dl_free(ue_dl_t *q);
 
-LIBLTE_API int ue_dl_receive(ue_dl_t *q, 
+LIBLTE_API int ue_dl_decode(ue_dl_t *q, 
                              cf_t *sf_buffer, 
                              char *data, 
                              uint32_t sf_idx,
-                             uint32_t sfn, 
                              uint16_t rnti);
 
 #endif

lte/phy/include/liblte/phy/ue/ue_mib.h

@@ -0,0 +1,109 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#ifndef UE_MIB_
+#define UE_MIB_
+
+
+/************************************************************
+ * 
+ * This object decodes the MIB from the PBCH of an LTE signal. 
+ * 
+ * The function ue_mib_decode() shall be called multiple times, 
+ * each passing a number of samples multiple of 19200, sampled at 1.92 MHz
+ * (that is, 10 ms of samples). 
+ * 
+ * The function uses the sync_t object to find the PSS sequence and 
+ * decode the PBCH to obtain the MIB. 
+ * 
+ * The function returns 0 until the MIB is decoded. 
+ * 
+ * See ue_cell_detect.c for an example. 
+ * 
+ ************************************************************/
+
+#include <stdbool.h>
+
+#include "liblte/config.h"
+#include "liblte/phy/sync/sync.h"
+#include "liblte/phy/sync/cfo.h"
+#include "liblte/phy/ch_estimation/chest.h"
+#include "liblte/phy/phch/pbch.h"
+#include "liblte/phy/common/fft.h"
+
+#define MIB_FIND_THRESHOLD          0.6
+
+#define MIB_NOF_PORTS           2
+
+#define MIB_FRAME_SIZE          9600
+
+#define MIB_FRAME_UNALIGNED     -3
+#define MIB_FOUND                1
+#define MIB_NOTFOUND             0
+
+typedef struct LIBLTE_API {
+  sync_t sfind;
+  
+  uint32_t cell_id; 
+  
+  cf_t *slot1_symbols;
+  cf_t *ce[MIB_NOF_PORTS];
+  
+  lte_fft_t fft;
+  chest_t chest; 
+  pbch_t pbch; 
+  
+  uint32_t frame_cnt; 
+  uint32_t last_frame_trial; 
+} ue_mib_t;
+
+
+LIBLTE_API int ue_mib_init(ue_mib_t *q, 
+                           uint32_t cell_id, 
+                           lte_cp_t cp);
+
+LIBLTE_API void ue_mib_free(ue_mib_t *q);
+
+LIBLTE_API void ue_mib_reset(ue_mib_t *q);
+
+LIBLTE_API int ue_mib_decode(ue_mib_t *q,
+                             cf_t *signal, 
+                             uint32_t nsamples,
+                             pbch_mib_t *mib);
+
+LIBLTE_API void ue_mib_set_threshold(ue_mib_t *q, 
+                                            float threshold); 
+
+LIBLTE_API void ue_mib_reset(ue_mib_t *q);
+
+
+
+
+
+
+#endif // SYNC_FRAME_
+

lte/phy/include/liblte/phy/ue/ue_sync.h

@@ -36,57 +36,36 @@
 #include "liblte/phy/ch_estimation/chest.h"
 #include "liblte/phy/phch/pbch.h"
 #include "liblte/phy/common/fft.h"
-#include "liblte/phy/agc/agc.h"
 
 /**************************************************************
  *
- * This object automatically manages the cell association and
+ * This object automatically manages the cell synchronization procedure. 
- * synchronization procedure. By default, it associates with the 
- * CELL whose correlation peak to average ratio is the highest. 
- * 
- * TODO: Associate with arbitrary CELL ID
  * 
  * The main function is ue_sync_get_buffer(), which returns a pointer
  * to the aligned subframe of samples (before FFT). This function
  * should be called regularly, returning every 1 ms. It reads from the 
  * USRP, aligns the samples to the subframe and performs time/freq synch. 
  *
- * The function returns 0 during the cell association procedure, which includes
- * PSS/SSS synchronization, MIB decoding from the PBCH and sampling frequency
- * adjustment (according to signal bandwidth) and resynchronization. 
- * 
  * The function returns 1 when the signal is correctly acquired and the 
  * returned buffer is aligned with the subframe. 
  * 
- * 
  *************************************************************/
 
-typedef enum LIBLTE_API { SF_AGC, SF_FIND, SF_TRACK} ue_sync_state_t;
+typedef enum LIBLTE_API { SF_FIND, SF_TRACK} ue_sync_state_t;
-
-#define SYNC_PBCH_NOF_PRB       6
-#define SYNC_PBCH_NOF_PORTS     2
 
 #define TRACK_MAX_LOST          10
-
-#define DEFAULT_NOF_MIB_DECODES 10
-
-#define AGC_NOF_FRAMES          100
-
 #define MEASURE_EXEC_TIME 
 
 typedef struct LIBLTE_API {
-  sync_t s;
+  sync_t sfind;
+  sync_t strack;
 
   void *stream; 
-  double (*set_rate_callback)(void*, double);
   int (*recv_callback)(void*, void*, uint32_t); 
 
   ue_sync_state_t state;
   
   cf_t *input_buffer; 
-  cf_t *receive_buffer; 
-  cf_t *sf_symbols; 
-  cf_t *ce[SYNC_PBCH_NOF_PORTS];
   
   /* These count half frames (5ms) */
   uint64_t frame_ok_cnt;
@@ -102,20 +81,6 @@ typedef struct LIBLTE_API {
   cfo_t cfocorr;
   float cur_cfo;
     
-  /* Variables for PBCH decoding */
-  agc_t agc;
-  pbch_mib_t mib; 
-  lte_fft_t fft; 
-  chest_t chest; 
-  pbch_t pbch; 
-  bool pbch_initialized; 
-  uint32_t pbch_decoded; 
-  bool pbch_decode_always; 
-  bool pbch_decoder_enabled;
-  uint32_t pbch_last_trial;
-  bool change_srate; 
-  uint32_t nof_mib_decodes; 
-  
   bool decode_sss_on_track; 
   
   uint32_t peak_idx;
@@ -128,7 +93,7 @@ typedef struct LIBLTE_API {
 
 
 LIBLTE_API int ue_sync_init(ue_sync_t *q, 
-                               double (set_rate_callback)(void*, double),
+                               lte_cell_t cell,
                                int (recv_callback)(void*, void*, uint32_t), 
                                void *stream_handler);
 
@@ -137,34 +102,15 @@ LIBLTE_API void ue_sync_free(ue_sync_t *q);
 LIBLTE_API int ue_sync_get_buffer(ue_sync_t *q, 
                                   cf_t **sf_symbols);
 
-LIBLTE_API void ue_sync_set_nof_pbch_decodes(ue_sync_t *q, 
-                                             uint32_t nof_pbch_decodes);
-
-
 LIBLTE_API void ue_sync_reset(ue_sync_t *q);
 
 LIBLTE_API void ue_sync_decode_sss_on_track(ue_sync_t *q, 
                                             bool enabled);
 
-LIBLTE_API void ue_sync_pbch_enable(ue_sync_t *q, 
-                                    bool enabled); 
-
-LIBLTE_API void ue_sync_change_srate(ue_sync_t *q, 
-                                     bool enabled);
-
-LIBLTE_API void ue_sync_pbch_always(ue_sync_t *q, 
-                                    bool enabled); 
-
 LIBLTE_API ue_sync_state_t ue_sync_get_state(ue_sync_t *q);
 
 LIBLTE_API uint32_t ue_sync_get_sfidx(ue_sync_t *q);
 
-LIBLTE_API lte_cell_t ue_sync_get_cell(ue_sync_t *q);
-
-LIBLTE_API pbch_mib_t ue_sync_get_mib(ue_sync_t *q);
-
-LIBLTE_API bool ue_sync_is_mib_decoded(ue_sync_t *q); 
-
 LIBLTE_API float ue_sync_get_cfo(ue_sync_t *q);
 
 LIBLTE_API float ue_sync_get_sfo(ue_sync_t *q);

lte/phy/include/liblte/phy/utils/vector.h

@@ -35,6 +35,9 @@
 
 typedef _Complex float cf_t;
 
+#define EXPAVERAGE(data, average, nframes) ((data + average * nframes) / (nframes + 1))  
+
+
 /** Return the sum of all the elements */
 LIBLTE_API int vec_acc_ii(int *x, uint32_t len);
 LIBLTE_API float vec_acc_ff(float *x, uint32_t len);
@@ -69,6 +72,7 @@ LIBLTE_API void vec_sc_prod_fff(float *x, float h, float *z, uint32_t len);
 LIBLTE_API void vec_convert_fi(float *x, int16_t *z, float scale, uint32_t len);
 
 LIBLTE_API void vec_deinterleave_cf(cf_t *x, float *real, float *imag, uint32_t len); 
+LIBLTE_API void vec_deinterleave_real_cf(cf_t *x, float *real, uint32_t len);
 
 /* vector product (element-wise) */
 LIBLTE_API void vec_prod_ccc(cf_t *x, cf_t *y, cf_t *z, uint32_t len);
@@ -95,6 +99,7 @@ LIBLTE_API float vec_avg_power_cf(cf_t *x, uint32_t len);
 
 /* return the index of the maximum value in the vector */
 LIBLTE_API uint32_t vec_max_fi(float *x, uint32_t len);
+LIBLTE_API uint32_t vec_max_abs_ci(cf_t *x, uint32_t len);
 
 /* quantify vector of floats and convert to unsigned char */
 LIBLTE_API void vec_quant_fuc(float *in, unsigned char *out, float gain, float offset, float clip, uint32_t len);

lte/phy/lib/ch_estimation/src/chest.c

@@ -38,7 +38,7 @@
 #define SLOT_SZ(q) (q->nof_symbols * q->symbol_sz)
 #define SF_SZ(q) (2 * SLOT_SZ(q))
 
-//#define VOLK_INTERP
+#define VOLK_INTERP
 
 void chest_fprint(chest_t *q, FILE *stream, uint32_t nslot, uint32_t port_id) {
   chest_ref_fprint(q, stream, nslot, port_id);
@@ -111,16 +111,18 @@ int chest_ce_ref(chest_t *q, cf_t *input, uint32_t nslot, uint32_t port_id, uint
       channel_ref = input[tidx * q->nof_re + fidx];
       q->refsignal[port_id][nslot].refs[nref].recv_simbol = channel_ref;
 
+      
       DEBUG("Reference %2d pos (%2d,%2d)=%3d %.2f dB %.2f/%.2f=%.2f\n", nref, tidx, fidx, tidx * q->nof_re + fidx,          
             10*log10f(cabsf(channel_ref/known_ref)),          
             cargf(channel_ref)/M_PI,cargf(known_ref)/M_PI,
             cargf(channel_ref/known_ref)/M_PI);
       
+      
       /* FIXME: compare with threshold */
       if (channel_ref != 0) {
         q->refsignal[port_id][nslot].ch_est[nref] = channel_ref/known_ref;
       } else {
-        q->refsignal[port_id][nslot].ch_est[nref] = 0;
+        q->refsignal[port_id][nslot].ch_est[nref] = 1e-6;
       }
       ret = LIBLTE_SUCCESS;
     }
@@ -145,7 +147,7 @@ int chest_ce_slot_port(chest_t *q, cf_t *input, cf_t *ce, uint32_t nslot, uint32
     if (q->refsignal[port_id][nslot].nsymbols <= 2) {
       refsignal_t *r = &q->refsignal[port_id][nslot];
 
-      INFO("Estimating channel slot=%d port=%d using %d reference signals\n",
+      DEBUG("Estimating channel slot=%d port=%d using %d reference signals\n",
           nslot, port_id, r->nof_refs);
 
       for (i=0;i<r->nof_refs;i++) {
@@ -276,6 +278,7 @@ int chest_ref_LTEDL_slot_port(chest_t *q, uint32_t nslot, uint32_t port_id, lte_
   {
     ret = refsignal_init_LTEDL(&q->refsignal[port_id][nslot], port_id, nslot, cell);
     
+#ifdef VOLK_INTERP
     if (ret == LIBLTE_SUCCESS) {
       if (nslot == 0) {
         ret = interp_init(&q->interp_freq[port_id], LINEAR, q->refsignal[port_id][nslot].nof_refs/2, RE_X_RB/2);
@@ -285,6 +288,7 @@ int chest_ref_LTEDL_slot_port(chest_t *q, uint32_t nslot, uint32_t port_id, lte_
         }
       }
     }
+#endif
   }
   return ret;
 }
@@ -318,6 +322,12 @@ void chest_free(chest_t *q) {
       refsignal_free(&q->refsignal[p][n]);
     }
   }
+#ifdef VOLK_INTERP
+  for (p=0;p<MAX_PORTS;p++) {
+    interp_free(&q->interp_freq[p]);
+    interp_free(&q->interp_time[p]);    
+  }
+#endif
   bzero(q, sizeof(chest_t));
 }
 

lte/phy/lib/channel/src/ch_awgn.c

@@ -29,25 +29,31 @@
 #include <complex.h>
 #include <stdlib.h>
 #include <strings.h>
+#include <math.h>
 
 #include "gauss.h"
 #include "liblte/phy/channel/ch_awgn.h"
 
-void ch_awgn_c(const cf_t* x, cf_t* y, float variance, int buff_sz) {
+float ch_awgn_get_variance(float ebno_db, float rate) {
-  _Complex float tmp;
+  float esno_db = ebno_db + 10 * log10f(rate);
-  int i;
+  return sqrtf(1 / (powf(10, esno_db / 10)));
+}
+
+void ch_awgn_c(const cf_t* x, cf_t* y, float variance, uint32_t len) {
+  cf_t tmp;
+  uint32_t i;
 
-  for (i=0;i<buff_sz;i++) {
+  for (i=0;i<len;i++) {
     __real__ tmp = rand_gauss();
     __imag__ tmp = rand_gauss();
     tmp *= variance;
     y[i] = tmp + x[i];
   }
 }
-void ch_awgn_f(const float* x, float* y, float variance, int buff_sz) {
+void ch_awgn_f(const float* x, float* y, float variance, uint32_t len) {
-  int i;
+  uint32_t i;
 
-  for (i=0;i<buff_sz;i++) {
+  for (i=0;i<len;i++) {
     y[i] = x[i] + variance * rand_gauss();
   }
 }

lte/phy/lib/common/src/fft.c

@@ -61,7 +61,7 @@ int lte_fft_init_(lte_fft_t *q, lte_cp_t cp, uint32_t nof_prb, dft_dir_t dir) {
   q->cp = cp;
   q->nof_re = nof_prb * RE_X_RB;
   q->nof_guards = ((symbol_sz - q->nof_re) / 2);
-  q->slot_sz = SLOT_LEN(symbol_sz, cp);
+  q->slot_sz = SLOT_LEN(symbol_sz);
   
   DEBUG("Init %s symbol_sz=%d, nof_symbols=%d, cp=%s, nof_re=%d, nof_guards=%d\n",
       dir==FORWARD?"FFT":"iFFT", q->symbol_sz, q->nof_symbols,

lte/phy/lib/common/test/fft_test.c

@@ -87,7 +87,7 @@ int main(int argc, char **argv) {
       perror("malloc");
       exit(-1);
     }
-    outfft = malloc(sizeof(cf_t) * SLOT_LEN_CPNORM(lte_symbol_sz(n_prb)));
+    outfft = malloc(sizeof(cf_t) * SLOT_LEN(lte_symbol_sz(n_prb)));
     if (!outfft) {
       perror("malloc");
       exit(-1);

lte/phy/lib/fec/src/turbodecoder.c

@@ -30,6 +30,7 @@
 #include <stdint.h>
 #include <string.h>
 #include <strings.h>
+#include <math.h>
 
 #include "liblte/phy/fec/turbodecoder.h"
 
@@ -39,7 +40,9 @@
  *  Decoder
  *
  ************************************************/
-void map_gen_beta(map_gen_t *s, llr_t *input, llr_t *parity, uint32_t long_cb) {
+void map_gen_beta(map_gen_t * s, llr_t * input, llr_t * parity,
+                  uint32_t long_cb)
+{
   llr_t m_b[8], new[8], old[8];
   llr_t x, y, xy;
   int k;
@@ -85,7 +88,8 @@ void map_gen_beta(map_gen_t *s, llr_t *input, llr_t *parity, uint32_t long_cb) {
 }
 
 void map_gen_alpha(map_gen_t * s, llr_t * input, llr_t * parity, llr_t * output,
-    uint32_t long_cb) {
+                   uint32_t long_cb)
+{
   llr_t m_b[8], new[8], old[8], max1[8], max0[8];
   llr_t m1, m0;
   llr_t x, y, xy;
@@ -150,7 +154,8 @@ void map_gen_alpha(map_gen_t *s, llr_t *input, llr_t *parity, llr_t *output,
   }
 }
 
-int map_gen_init(map_gen_t *h, int max_long_cb) {
+int map_gen_init(map_gen_t * h, int max_long_cb)
+{
   bzero(h, sizeof(map_gen_t));
   h->beta = malloc(sizeof(llr_t) * (max_long_cb + TOTALTAIL + 1) * NUMSTATES);
   if (!h->beta) {
@@ -161,7 +166,8 @@ int map_gen_init(map_gen_t *h, int max_long_cb) {
   return 0;
 }
 
-void map_gen_free(map_gen_t *h) {
+void map_gen_free(map_gen_t * h)
+{
   if (h->beta) {
     free(h->beta);
   }
@@ -169,7 +175,8 @@ void map_gen_free(map_gen_t *h) {
 }
 
 void map_gen_dec(map_gen_t * h, llr_t * input, llr_t * parity, llr_t * output,
-    uint32_t long_cb) {
+                 uint32_t long_cb)
+{
   uint32_t k;
 
   h->beta[(long_cb + TAIL) * NUMSTATES] = 0;
@@ -185,7 +192,8 @@ void map_gen_dec(map_gen_t *h, llr_t *input, llr_t *parity, llr_t *output,
  *  TURBO DECODER INTERFACE
  *
  ************************************************/
-int tdec_init(tdec_t *h, uint32_t max_long_cb) {
+int tdec_init(tdec_t * h, uint32_t max_long_cb)
+{
   int ret = -1;
   bzero(h, sizeof(tdec_t));
   uint32_t len = max_long_cb + TOTALTAIL;
@@ -233,7 +241,8 @@ int tdec_init(tdec_t *h, uint32_t max_long_cb) {
   return ret;
 }
 
-void tdec_free(tdec_t *h) {
+void tdec_free(tdec_t * h)
+{
   if (h->llr1) {
     free(h->llr1);
   }
@@ -257,7 +266,8 @@ void tdec_free(tdec_t *h) {
   bzero(h, sizeof(tdec_t));
 }
 
-void tdec_iteration(tdec_t *h, llr_t *input, uint32_t long_cb) {
+void tdec_iteration(tdec_t * h, llr_t * input, uint32_t long_cb)
+{
   uint32_t i;
 
   // Prepare systematic and parity bits for MAP DEC #1
@@ -296,25 +306,28 @@ void tdec_iteration(tdec_t *h, llr_t *input, uint32_t long_cb) {
 
 }
 
-int tdec_reset(tdec_t *h, uint32_t long_cb) {
+int tdec_reset(tdec_t * h, uint32_t long_cb)
-  memset(h->w, 0, sizeof(llr_t) * long_cb);
+{
   if (long_cb > h->max_long_cb) {
     fprintf(stderr, "TDEC was initialized for max_long_cb=%d\n",
             h->max_long_cb);
     return -1;
   }
+  memset(h->w, 0, sizeof(llr_t) * long_cb);
   return tc_interl_LTE_gen(&h->interleaver, long_cb);
 }
 
-void tdec_decision(tdec_t *h, char *output, uint32_t long_cb) {
+void tdec_decision(tdec_t * h, char *output, uint32_t long_cb)
+{
   uint32_t i;
   for (i = 0; i < long_cb; i++) {
     output[i] = (h->llr2[h->interleaver.reverse[i]] > 0) ? 1 : 0;    
   }
 }
 
-void tdec_run_all(tdec_t *h, llr_t *input, char *output, uint32_t nof_iterations,
+void tdec_run_all(tdec_t * h, llr_t * input, char *output,
-    uint32_t long_cb) {
+                  uint32_t nof_iterations, uint32_t long_cb)
+{
   uint32_t iter = 0;
 
   tdec_reset(h, long_cb);
@@ -326,4 +339,3 @@ void tdec_run_all(tdec_t *h, llr_t *input, char *output, uint32_t nof_iterations
 
   tdec_decision(h, output, long_cb);
 }
-

lte/phy/lib/mimo/src/precoding.c

@@ -124,6 +124,11 @@ int precoding_type(cf_t *x[MAX_LAYERS], cf_t *y[MAX_PORTS], int nof_layers,
 
 /* ZF detector */
 int predecoding_single_zf(cf_t *y, cf_t *ce, cf_t *x, int nof_symbols) {
+  for (int i=0;i<nof_symbols;i++) {
+    if (ce[i] == 0) {
+      ce[i] = 0.01;
+    }
+  }
   vec_div_ccc(y, ce, x, nof_symbols);
   return nof_symbols;
 }
@@ -143,6 +148,9 @@ int predecoding_diversity_zf(cf_t *y, cf_t *ce[MAX_PORTS], cf_t *x[MAX_LAYERS],
           + crealf(h1) * crealf(h1) + cimagf(h1) * cimagf(h1);
       r0 = y[2 * i];
       r1 = y[2 * i + 1];
+      if (hh == 0) {
+        hh = 1e-2;
+      }
       x[0][i] = (conjf(h0) * r0 + h1 * conjf(r1)) / hh * sqrt(2);
       x[1][i] = (-h1 * conj(r0) + conj(h0) * r1) / hh * sqrt(2);
     }

lte/phy/lib/modem/src/demod_soft.c

@@ -36,6 +36,7 @@
 
 void demod_soft_init(demod_soft_t *q) {
   bzero((void*)q,sizeof(demod_soft_t));
+  q->sigma = 1.0; 
 }
 
 void demod_soft_table_set(demod_soft_t *q, modem_table_t *table) {

lte/phy/lib/modem/src/soft_algs.c

@@ -34,6 +34,54 @@
 
 #include "soft_algs.h"
 
+#define LLR_APPROX_USE_VOLK
+
+
+#ifdef LLR_APPROX_USE_VOLK
+void
+llr_approx(const _Complex float *in, float *out, int N, int M, int B,
+           _Complex float *symbols, uint32_t(*S)[6][32], float sigma2)
+{
+  int i, s, b;
+  float num, den;
+  int change_sign = -1;
+  float x, y, d[64];
+
+  for (s = 0; s < N; s++) {     /* recevied symbols */
+    /* Compute the distances squared d[i] between the received symbol and all constellation points */
+    for (i = 0; i < M; i++) {
+      x = __real__ in[s] - __real__ symbols[i];
+      y = __imag__ in[s] - __imag__ symbols[i];
+      d[i] = x * x + y * y;
+    }
+
+    for (b = 0; b < B; b++) {   /* bits per symbol */
+      /* initiate num[b] and den[b] */
+      num = d[S[0][b][0]];
+      den = d[S[1][b][0]];
+
+      /* Minimum distance squared search between recevied symbol and a constellation point with a
+         '1' and a '0' for each bit position */
+      for (i = 1; i < M / 2; i++) {     /* half the constellation points have '1'|'0' at any given bit position */
+        if (d[S[0][b][i]] < num) {
+          num = d[S[0][b][i]];
+        }
+        if (d[S[1][b][i]] < den) {
+          den = d[S[1][b][i]];
+        }
+      }
+      /* Theoretical LLR and approximate LLR values are positive if
+       * symbol(s) with '0' is/are closer and negative if symbol(s)
+       * with '1' are closer.
+       * Change sign if mapping negative to '0' and positive to '1' */
+      out[s * B + b] = change_sign * (den - num) / sigma2;
+    }
+  }
+
+}
+
+#else 
+
 /**
  * @ingroup Soft Modulation Demapping based on the approximate
  * log-likelihood algorithm
@@ -50,8 +98,10 @@
  * \param S Soft demapping auxiliary matrix
  * \param sigma2 Noise vatiance
  */
-void llr_approx(const _Complex float *in, float *out, int N, int M, int B,
+void
-    _Complex float *symbols, uint32_t (*S)[6][32], float sigma2) {
+llr_approx(const _Complex float *in, float *out, int N, int M, int B,
+           _Complex float *symbols, uint32_t(*S)[6][32], float sigma2)
+{
   int i, s, b;
   float num, den;
   int change_sign = -1;
@@ -90,6 +140,8 @@ void llr_approx(const _Complex float *in, float *out, int N, int M, int B,
 
 }
 
+#endif
+
 /**
  * @ingroup Soft Modulation Demapping based on the approximate
  * log-likelihood ratio algorithm
@@ -107,7 +159,8 @@ void llr_approx(const _Complex float *in, float *out, int N, int M, int B,
  * \param sigma2 Noise vatiance
  */
 void llr_exact(const _Complex float *in, float *out, int N, int M, int B,
-    _Complex float *symbols, uint32_t (*S)[6][32], float sigma2) {
+          _Complex float *symbols, uint32_t(*S)[6][32], float sigma2)
+{
   int i, s, b;
   float num, den;
   int change_sign = -1;

lte/phy/lib/modem/test/CMakeLists.txt

@@ -36,5 +36,13 @@ ADD_TEST(modem_qpsk_soft modem_test -n 1020 -m 2 -s)
 ADD_TEST(modem_qam16_soft modem_test -n 1020 -m 4 -s)
 ADD_TEST(modem_qam64_soft modem_test -n 1020 -m 6 -s)
  
+ADD_EXECUTABLE(soft_demod_test soft_demod_test.c)
+TARGET_LINK_LIBRARIES(soft_demod_test lte_phy)
+
+ADD_TEST(modem_bpsk_soft_approx soft_demod_test -n 1020 -m 1) 
+ADD_TEST(modem_qpsk_soft_approx soft_demod_test -n 1020 -m 2)
+ADD_TEST(modem_qam16_soft_approx soft_demod_test -n 1020 -m 4)
+ADD_TEST(modem_qam64_soft_approx soft_demod_test -n 1020 -m 6)
+ 
 
 

lte/phy/lib/modem/test/soft_demod_test.c

@@ -0,0 +1,229 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <math.h>
+#include <time.h>
+#include <stdbool.h>
+
+#include "liblte/phy/phy.h"
+
+int nof_frames = 10; 
+int num_bits = 1000;
+lte_mod_t modulation = 0;
+
+void usage(char *prog) {
+  printf("Usage: %s [nfv] -m modulation (1: BPSK, 2: QPSK, 4: QAM16, 6: QAM64)\n", prog);
+  printf("\t-n num_bits [Default %d]\n", num_bits);
+  printf("\t-f nof_frames [Default %d]\n", nof_frames);
+  printf("\t-v verbose [Default None]\n");
+}
+
+void parse_args(int argc, char **argv) {
+  int opt;
+  while ((opt = getopt(argc, argv, "nmvf")) != -1) {
+    switch (opt) {
+    case 'n':
+      num_bits = atoi(argv[optind]);
+      break;
+    case 'f':
+      nof_frames = atoi(argv[optind]);
+      break;
+    case 'v':
+      verbose++;
+      break;
+    case 'm':
+      switch(atoi(argv[optind])) {
+      case 1:
+        modulation = LTE_BPSK;
+        break;
+      case 2:
+        modulation = LTE_QPSK;
+        break;
+      case 4:
+        modulation = LTE_QAM16;
+        break;
+      case 6:
+        modulation = LTE_QAM64;
+        break;
+      default:
+        fprintf(stderr, "Invalid modulation %d. Possible values: "
+            "(1: BPSK, 2: QPSK, 4: QAM16, 6: QAM64)\n", atoi(argv[optind]));
+        break;
+      }
+      break;
+    default:
+      usage(argv[0]);
+      exit(-1);
+    }
+  }
+  if (modulation == 0) {
+    usage(argv[0]);
+    exit(-1);
+  }
+}
+
+float mse_threshold() {
+  switch(modulation) {
+    case LTE_BPSK: 
+      return 1.0e-6;
+    case LTE_QPSK:
+      return 1.0e-6; 
+    case LTE_QAM16: 
+      return 0.11; 
+    case LTE_QAM64:
+      return 0.18;
+    default:
+      return -1.0;
+  }
+}
+
+int main(int argc, char **argv) {
+  int i;
+  modem_table_t mod;
+  demod_soft_t demod_soft;
+  char *input, *output;
+  cf_t *symbols;
+  float *llr_exact, *llr_approx;
+
+  parse_args(argc, argv);
+
+  /* initialize objects */
+  if (modem_table_lte(&mod, modulation, true)) {
+    fprintf(stderr, "Error initializing modem table\n");
+    exit(-1);
+  }
+
+  /* check that num_bits is multiple of num_bits x symbol */
+  num_bits = mod.nbits_x_symbol * (num_bits / mod.nbits_x_symbol);
+
+  demod_soft_init(&demod_soft);
+  demod_soft_table_set(&demod_soft, &mod);
+  demod_soft_sigma_set(&demod_soft, 2.0 / mod.nbits_x_symbol);
+
+  /* allocate buffers */
+  input = malloc(sizeof(char) * num_bits);
+  if (!input) {
+    perror("malloc");
+    exit(-1);
+  }
+  output = malloc(sizeof(char) * num_bits);
+  if (!output) {
+    perror("malloc");
+    exit(-1);
+  }
+  symbols = malloc(sizeof(cf_t) * num_bits / mod.nbits_x_symbol);
+  if (!symbols) {
+    perror("malloc");
+    exit(-1);
+  }
+
+  llr_exact = malloc(sizeof(float) * num_bits);
+  if (!llr_exact) {
+    perror("malloc");
+    exit(-1);
+  }
+
+  llr_approx = malloc(sizeof(float) * num_bits);
+  if (!llr_approx) {
+    perror("malloc");
+    exit(-1);
+  }
+
+  /* generate random data */
+  srand(time(NULL));
+  
+  int ret = -1;
+  double mse;
+  struct timeval t[3]; 
+  float mean_texec = 0.0; 
+  for (int n=0;n<nof_frames;n++) {
+    for (i=0;i<num_bits;i++) {
+      input[i] = rand()%2;
+    }
+
+    /* modulate */
+    mod_modulate(&mod, input, symbols, num_bits);
+
+    /* add noise */
+    ch_awgn_c(symbols, symbols, ch_awgn_get_variance(5.0, mod.nbits_x_symbol), num_bits / mod.nbits_x_symbol);
+    
+    /* Compare exact with approximation algorithms */
+    demod_soft_alg_set(&demod_soft, EXACT);
+    demod_soft_demodulate(&demod_soft, symbols, llr_exact, num_bits / mod.nbits_x_symbol);
+    
+    demod_soft_alg_set(&demod_soft, APPROX);
+    gettimeofday(&t[1], NULL);
+    demod_soft_demodulate(&demod_soft, symbols, llr_approx, num_bits / mod.nbits_x_symbol);
+    gettimeofday(&t[2], NULL);
+    get_time_interval(t);
+    
+    /* compute exponentially averaged execution time */
+    mean_texec = EXPAVERAGE((float) t[0].tv_usec, mean_texec, n);
+    
+    /* check MSE */
+    mse = 0.0;
+    for (i=0;i<num_bits;i++) {
+      float e = llr_exact[i] - llr_approx[i];
+      mse += e*e;
+    }
+    mse/=num_bits;
+
+    if (VERBOSE_ISDEBUG()) {
+      printf("exact=");
+      vec_fprint_f(stdout, llr_exact, num_bits);
+
+      printf("approx=");
+      vec_fprint_f(stdout, llr_approx, num_bits);
+    }
+    
+    if (mse > mse_threshold()) {
+        goto clean_exit; 
+    }
+  }
+  ret = 0; 
+
+clean_exit:  
+  free(llr_exact);
+  free(llr_approx);
+  free(symbols);
+  free(output);
+  free(input);
+
+  modem_table_free(&mod);
+
+  if (ret == 0) {
+    printf("Ok Mean Throughput: %.2f. Mbps ExTime: %.2f us\n", num_bits/mean_texec, mean_texec);    
+  } else {
+    printf("Error: MSE too large (%f > %f)\n", mse, mse_threshold());
+  }
+  exit(ret);
+}

lte/phy/lib/phch/src/pbch.c

@@ -453,30 +453,25 @@ int pbch_decode_frame(pbch_t *q, pbch_mib_t *mib, uint32_t src, uint32_t dst, ui
  *
  * Returns 1 if successfully decoded MIB, 0 if not and -1 on error
  */
-int pbch_decode(pbch_t *q, cf_t *sf_symbols, cf_t *ce[MAX_PORTS], pbch_mib_t *mib) {
+int pbch_decode(pbch_t *q, cf_t *slot1_symbols, cf_t *ce_slot1[MAX_PORTS], pbch_mib_t *mib) {
   uint32_t src, dst, nb;
   uint32_t nant_[3] = { 1, 2, 4 };
   uint32_t na, nant;
-  cf_t *slot1_symbols;
   int i;
   int nof_bits;
   cf_t *x[MAX_LAYERS];
-  cf_t *ce_slot[MAX_PORTS];
   
   int ret = LIBLTE_ERROR_INVALID_INPUTS;
   
   if (q                 != NULL &&
-      sf_symbols        != NULL && 
+      slot1_symbols        != NULL && 
       mib               != NULL)
   {
     for (i=0;i<q->cell.nof_ports;i++) {
-      if (ce[i] == NULL) {
+      if (ce_slot1[i] == NULL) {
         return LIBLTE_ERROR_INVALID_INPUTS;
-      } else {
-        ce_slot[i] = &ce[i][q->cell.nof_prb * RE_X_RB * CP_NSYMB(q->cell.cp)];
       } 
     }
-    slot1_symbols = &sf_symbols[q->cell.nof_prb * RE_X_RB * CP_NSYMB(q->cell.cp)];
 
     /* Set pointers for layermapping & precoding */
     nof_bits = 2 * q->nof_symbols;
@@ -495,7 +490,7 @@ int pbch_decode(pbch_t *q, cf_t *sf_symbols, cf_t *ce[MAX_PORTS], pbch_mib_t *mi
 
     /* extract channel estimates */
     for (i = 0; i < q->cell.nof_ports; i++) {
-      if (q->nof_symbols != pbch_get(ce_slot[i], q->ce[i], q->cell)) {
+      if (q->nof_symbols != pbch_get(ce_slot1[i], q->ce[i], q->cell)) {
         fprintf(stderr, "There was an error getting the PBCH symbols\n");
         return LIBLTE_ERROR;
       }
@@ -508,7 +503,7 @@ int pbch_decode(pbch_t *q, cf_t *sf_symbols, cf_t *ce[MAX_PORTS], pbch_mib_t *mi
     for (na = 0; na < q->cell.nof_ports && !ret; na++) {
       nant = nant_[na];
 
-      INFO("Trying %d TX antennas with %d frames\n", nant, q->frame_idx);
+      DEBUG("Trying %d TX antennas with %d frames\n", nant, q->frame_idx);
 
       /* in conctrol channels, only diversity is supported */
       if (nant == 1) {
@@ -554,20 +549,17 @@ int pbch_decode(pbch_t *q, cf_t *sf_symbols, cf_t *ce[MAX_PORTS], pbch_mib_t *mi
 
 /** Converts the MIB message to symbols mapped to SLOT #1 ready for transmission
  */
-int pbch_encode(pbch_t *q, pbch_mib_t *mib, cf_t *sf_symbols[MAX_PORTS]) {
+int pbch_encode(pbch_t *q, pbch_mib_t *mib, cf_t *slot1_symbols[MAX_PORTS]) {
   int i;
   int nof_bits;
-  cf_t *slot1_symbols[MAX_PORTS];
   cf_t *x[MAX_LAYERS];
   
   if (q                 != NULL &&
       mib               != NULL)
   {
     for (i=0;i<q->cell.nof_ports;i++) {
-      if (sf_symbols[i] == NULL) {
+      if (slot1_symbols[i] == NULL) {
         return LIBLTE_ERROR_INVALID_INPUTS;
-      } else {
-        slot1_symbols[i] = &sf_symbols[i][q->cell.nof_prb * RE_X_RB * CP_NSYMB(q->cell.cp)];
       } 
     }
     /* Set pointers for layermapping & precoding */

lte/phy/lib/phch/src/pdsch.c

@@ -183,7 +183,7 @@ int pdsch_init(pdsch_t *q, lte_cell_t cell) {
     ret = LIBLTE_ERROR;
     
     q->cell = cell;
-    
+    q->average_nof_iterations_n = 0; 
     q->max_symbols = q->cell.nof_prb * MAX_PDSCH_RE(q->cell.cp);
 
     INFO("Init PDSCH: %d ports %d PRBs, max_symbols: %d\n", q->cell.nof_ports,
@@ -459,6 +459,15 @@ int pdsch_harq_setup(pdsch_harq_t *p, ra_mcs_t mcs, ra_prb_t *prb_alloc) {
 }
 
 
+float pdsch_average_noi(pdsch_t *q) {
+  return q->average_nof_iterations; 
+}
+
+uint32_t pdsch_last_noi(pdsch_t *q) {
+  return q->nof_iterations;
+}
+
+
 /* Decode a transport block according to 36.212 5.3.2
  *
  */
@@ -508,6 +517,7 @@ int pdsch_decode_tb(pdsch_t *q, char *data, uint32_t tbs, uint32_t nb_e,
       DEBUG("CB#%d: cb_len: %d, rlen: %d, wp: %d, rp: %d, F: %d, E: %d\n", i,
           cb_len, rlen - F, wp, rp, F, n_e);
 
+      
       /* Rate Unmatching */
       if (rm_turbo_rx(harq_process->pdsch_w_buff_f[i], harq_process->w_buff_size,  
                   &e_bits[rp], n_e, 
@@ -516,24 +526,51 @@ int pdsch_decode_tb(pdsch_t *q, char *data, uint32_t tbs, uint32_t nb_e,
         return LIBLTE_ERROR;
       }
 
-      /* Turbo Decoding */
+      /* Turbo Decoding with CRC-based early stopping */
-      tdec_run_all(&q->decoder, (float*) q->cb_out, q->cb_in, TDEC_ITERATIONS,
+      q->nof_iterations = 0; 
-          cb_len);
+      bool early_stop = false;
+      uint32_t len_crc; 
+      char *cb_in_ptr; 
+      crc_t *crc_ptr; 
+      tdec_reset(&q->decoder, cb_len);
+            
+      do {
+        
+        tdec_iteration(&q->decoder, (float*) q->cb_out, cb_len); 
+        q->nof_iterations++;
         
         if (harq_process->cb_segm.C > 1) {
-        /* Check Codeblock CRC and stop early if incorrect */
+          len_crc = cb_len; 
-        if (crc_checksum(&q->crc_cb, q->cb_in, cb_len)) {
+          cb_in_ptr = q->cb_in; 
-          INFO("Error in CB#%d\n",i);
+          crc_ptr = &q->crc_cb; 
-          return LIBLTE_ERROR;
+        } else {
+          len_crc = tbs+24; 
+          bzero(q->cb_in, F*sizeof(char));
+          cb_in_ptr = &q->cb_in[F];
+          crc_ptr = &q->crc_tb; 
         }
+
+        tdec_decision(&q->decoder, q->cb_in, cb_len);
+  
+        /* Check Codeblock CRC and stop early if incorrect */
+        if (!crc_checksum(crc_ptr, cb_in_ptr, len_crc)) {
+          early_stop = true;           
         }
         
+      } while (q->nof_iterations < TDEC_MAX_ITERATIONS && !early_stop);
+            
+      q->average_nof_iterations = EXPAVERAGE((float) q->nof_iterations, 
+                                             q->average_nof_iterations, 
+                                             q->average_nof_iterations_n);
+      q->average_nof_iterations_n++;
+
       /* Copy data to another buffer, removing the Codeblock CRC */
       if (i < harq_process->cb_segm.C - 1) {
         memcpy(&data[wp], &q->cb_in[F], (rlen - F) * sizeof(char));
       } else {
         DEBUG("Last CB, appending parity: %d to %d from %d and 24 from %d\n",
             rlen - F - 24, wp, F, rlen - 24);
+        
         /* Append Transport Block parity bits to the last CB */
         memcpy(&data[wp], &q->cb_in[F], (rlen - F - 24) * sizeof(char));
         memcpy(parity, &q->cb_in[rlen - 24], 24 * sizeof(char));
@@ -637,6 +674,19 @@ int pdsch_decode(pdsch_t *q, cf_t *sf_symbols, cf_t *ce[MAX_PORTS], char *data,
     demod_soft_table_set(&q->demod, &q->mod[harq_process->mcs.mod - 1]);
     demod_soft_demodulate(&q->demod, q->pdsch_d, q->pdsch_e, nof_symbols);
  
+    /*
+    for (int j=0;j<nof_symbols;j++) {
+      if (isnan(crealf(q->pdsch_d[j])) || isnan(cimagf(q->pdsch_d[j]))) {
+        printf("\nerror in d[%d]=%f+%f symbols:%f+%f ce0:%f+%f ce1:%f+%f\n",j,
+               crealf(q->pdsch_d[j]), cimagf(q->pdsch_d[j]), 
+               crealf(q->pdsch_symbols[0][j]), cimagf(q->pdsch_symbols[0][j]), 
+               crealf(q->ce[0][j]), cimagf(q->ce[0][j]), 
+               crealf(q->ce[1][j]), cimagf(q->ce[1][j])
+              );
+      }
+    }
+    */
+
     /* descramble */
     scrambling_f_offset(&q->seq_pdsch[subframe], q->pdsch_e, 0, nof_bits_e);
     

lte/phy/lib/phch/src/ue_sync.c

@@ -1,628 +0,0 @@
-/**
- *
- * \section COPYRIGHT
- *
- * Copyright 2013-2014 The libLTE Developers. See the
- * COPYRIGHT file at the top-level directory of this distribution.
- *
- * \section LICENSE
- *
- * This file is part of the libLTE library.
- *
- * libLTE is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as
- * published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version.
- *
- * libLTE is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser General Public License for more details.
- *
- * A copy of the GNU Lesser General Public License can be found in
- * the LICENSE file in the top-level directory of this distribution
- * and at http://www.gnu.org/licenses/.
- *
- */
-
-#include <stdlib.h>
-#include <string.h>
-#include <strings.h>
-#include <assert.h>
-#include <unistd.h>
-
-
-#include "liblte/phy/phch/ue_sync.h"
-
-#include "liblte/phy/utils/debug.h"
-#include "liblte/phy/utils/vector.h"
-
-#define MAX_TIME_OFFSET 128
-cf_t dummy[MAX_TIME_OFFSET];
-
-#define EXPAVERAGE(data, average, nframes) ((data + average * nframes) / (nframes + 1))  
-
-#define CURRENT_FFTSIZE   lte_symbol_sz(q->cell.nof_prb)
-#define CURRENT_SFLEN     SF_LEN(CURRENT_FFTSIZE, q->cell.cp)
-
-#define CURRENT_SLOTLEN_RE SLOT_LEN_RE(q->cell.nof_prb, q->cell.cp)
-#define CURRENT_SFLEN_RE SF_LEN_RE(q->cell.nof_prb, q->cell.cp)
-
-#define MAXIMUM_SFLEN       SF_LEN(2048, CPNORM)
-#define MAXIMUM_SFLEN_RE    SF_LEN_RE(110, CPNORM)
-
-static int mib_decoder_initialize(ue_sync_t *q);
-static void mib_decoder_free(ue_sync_t *q);
-
-
-static void update_threshold(ue_sync_t *q) {
-  int symbol_sz = lte_symbol_sz(q->cell.nof_prb);
-  if (symbol_sz > 0) {
-    switch (symbol_sz) {
-      case 128:
-        sync_set_threshold(&q->s, 20000, 2000);
-        break;
-      case 256:
-        sync_set_threshold(&q->s, 25000, 2500);
-        break;
-      case 512:
-        sync_set_threshold(&q->s, 38000, 3800);
-        break;
-      case 1024:
-        sync_set_threshold(&q->s, 50000, 5000);
-        break;
-      case 2048:
-        sync_set_threshold(&q->s, 80000, 4000);
-    }  
-  }
-}
-
-int ue_sync_init(ue_sync_t *q, 
-                    double (set_rate_callback)(void*, double),
-                    int (recv_callback)(void*, void*, uint32_t),
-                    void *stream_handler) 
-{
-  int ret = LIBLTE_ERROR_INVALID_INPUTS;
-  
-  if (q                    != NULL && 
-      stream_handler       != NULL && 
-      set_rate_callback    != NULL &&
-      recv_callback        != NULL)
-  {
-    ret = LIBLTE_ERROR;
-    
-    bzero(q, sizeof(ue_sync_t));
-
-    ue_sync_reset(q);
-
-    q->cell.nof_prb = SYNC_PBCH_NOF_PRB;
-    q->cell.nof_ports = SYNC_PBCH_NOF_PORTS; 
-    q->cell.id = 0; 
-    q->cell.cp = CPNORM;
-    
-    q->pbch_decoded = false; 
-    q->pbch_initialized = false; 
-    q->pbch_decoder_enabled = true; 
-    q->pbch_decode_always = false; 
-    q->decode_sss_on_track = false; 
-    q->change_srate = true; 
-    q->nof_mib_decodes = DEFAULT_NOF_MIB_DECODES;
-    q->stream = stream_handler;
-    q->recv_callback = recv_callback;
-    q->set_rate_callback = set_rate_callback;
-    
-    INFO("Setting sampling frequency 1.92 MHz\n",0);
-    q->set_rate_callback(q->stream, 1920000.0);
-    
-    if (agc_init(&q->agc)) {
-      goto clean_exit;
-    }
-    
-    if(sync_init(&q->s, CURRENT_SFLEN, CURRENT_FFTSIZE, CURRENT_FFTSIZE)) {
-      goto clean_exit;
-    }
-    
-    sync_pss_det_absolute(&q->s);
-    
-    if (cfo_init(&q->cfocorr, MAXIMUM_SFLEN)) {
-      fprintf(stderr, "Error initiating CFO\n");
-      goto clean_exit;
-    }
-   
-    q->input_buffer = vec_malloc(3 * MAXIMUM_SFLEN * sizeof(cf_t));
-    if (!q->input_buffer) {
-      perror("malloc");
-      goto clean_exit;
-    }
-   
-    q->receive_buffer = vec_malloc(3 * MAXIMUM_SFLEN * sizeof(cf_t));
-    if (!q->receive_buffer) {
-      perror("malloc");
-      goto clean_exit;
-    }
-    
-    q->sf_symbols = vec_malloc(MAXIMUM_SFLEN_RE * sizeof(cf_t));
-    if (!q->sf_symbols) {
-      perror("malloc");
-      goto clean_exit; 
-    }
-    for (int i=0;i<SYNC_PBCH_NOF_PORTS;i++) {
-      q->ce[i] = vec_malloc(MAXIMUM_SFLEN_RE * sizeof(cf_t));
-      if (!q->ce[i]) {
-        perror("malloc");
-        goto clean_exit; 
-      }
-    }
-   
-    update_threshold(q);
-    
-    ret = LIBLTE_SUCCESS;
-  }
-  
-clean_exit:
-  if (ret == LIBLTE_ERROR) {
-    ue_sync_free(q);
-  }
-  return ret; 
-}
-
-void ue_sync_free(ue_sync_t *q) {
-  if (q->input_buffer) {
-    free(q->input_buffer);
-  }
-  if (q->receive_buffer) {
-    free(q->receive_buffer);
-  }
-  if (q->sf_symbols) {
-    free(q->sf_symbols);
-  }
-  for (int i=0;i<SYNC_PBCH_NOF_PORTS;i++) {
-    if (q->ce[i]) {
-      free(q->ce[i]);
-    }
-  }
-  mib_decoder_free(q);
-  cfo_free(&q->cfocorr);
-  sync_free(&q->s);
-  agc_free(&q->agc);
-}
-
-lte_cell_t ue_sync_get_cell(ue_sync_t *q) {
-  return q->cell;
-}
-
-pbch_mib_t ue_sync_get_mib(ue_sync_t *q) {
-  return q->mib;
-}
-
-uint32_t ue_sync_peak_idx(ue_sync_t *q) {
-  return q->peak_idx;
-}
-
-ue_sync_state_t ue_sync_get_state(ue_sync_t *q) {
-  return q->state;
-}
-
-void ue_sync_change_srate(ue_sync_t *q, bool enabled) {
-  q->change_srate = enabled; 
-}
-
-static int update_srate(ue_sync_t *q) {
-  struct timeval t[3];
-    
-  gettimeofday(&t[1], NULL);
-  if (sync_realloc(&q->s, CURRENT_SFLEN, CURRENT_FFTSIZE, CURRENT_FFTSIZE)) {
-    fprintf(stderr, "Error realloc'ing SYNC\n");
-    return LIBLTE_ERROR;
-  }
-  gettimeofday(&t[2], NULL);
-  get_time_interval(t);
-  
-  if (q->nof_mib_decodes > 1) {
-    mib_decoder_free(q);  
-    if (mib_decoder_initialize(q)) {
-      fprintf(stderr, "Error reinitializing MIB decoder\n");
-      return LIBLTE_ERROR; 
-    }
-  }  
-
-  // Finally set the new sampling rate
-  q->set_rate_callback(q->stream, (float) lte_sampling_freq_hz(q->cell.nof_prb));
- 
-  update_threshold(q);
-   
-  ue_sync_reset(q);
-  INFO("Set sampling rate %.2f MHz, fft_size=%d, sf_len=%d Threshold=%.2f/%.2f Texec=%d us\n", 
-       (float) lte_sampling_freq_hz(q->cell.nof_prb)/1000000, 
-       CURRENT_FFTSIZE, CURRENT_SFLEN, q->s.find_threshold, q->s.track_threshold, (int) t[0].tv_usec);
-  
-  return LIBLTE_SUCCESS;
-}
-
-uint32_t ue_sync_get_sfidx(ue_sync_t *q) {
-  return q->sf_idx;    
-}
-
-float ue_sync_get_cfo(ue_sync_t *q) {
-  return 15000 * q->cur_cfo;
-}
-
-float ue_sync_get_sfo(ue_sync_t *q) {
-  return 1000*q->mean_time_offset/5;
-}
-
-bool ue_sync_is_mib_decoded(ue_sync_t *q) {
-  return q->pbch_decoded;
-}
-
-void ue_sync_pbch_enable(ue_sync_t *q, bool enabled) {
-  q->pbch_decoder_enabled = enabled; 
-}
-
-void ue_sync_pbch_always(ue_sync_t *q, bool enabled) {
-  q->pbch_decode_always = enabled;
-}
-
-void ue_sync_decode_sss_on_track(ue_sync_t *q, bool enabled) {
-  q->decode_sss_on_track = enabled; 
-}
-
-void ue_sync_set_nof_pbch_decodes(ue_sync_t *q, uint32_t nof_pbch_decodes) {
-  q->nof_mib_decodes = nof_pbch_decodes;
-}
-
-static int mib_decoder_initialize(ue_sync_t *q) {
-    
-  if (lte_fft_init(&q->fft, q->cell.cp, q->cell.nof_prb)) {
-    fprintf(stderr, "Error initializing FFT\n");
-    return -1;
-  }
-  if (chest_init_LTEDL(&q->chest, q->cell)) {
-    fprintf(stderr, "Error initializing reference signal\n");
-    return -1;
-  }
-  if (pbch_init(&q->pbch, q->cell)) {
-    fprintf(stderr, "Error initiating PBCH\n");
-    return -1;
-  }
-  q->pbch_initialized = 1;
-  DEBUG("PBCH initiated cell_id=%d\n", q->cell.id);
-  
-  return 0;
-}
-
-static void mib_decoder_free(ue_sync_t *q) {
-  chest_free(&q->chest);
-  pbch_free(&q->pbch);
-  lte_fft_free(&q->fft);
-}
-
-static int mib_decoder_run(ue_sync_t *q) {
-  int ret; 
-  
-  /* Run FFT for the second slot */
-  lte_fft_run_sf(&q->fft, q->input_buffer, q->sf_symbols);
-
-  /* Get channel estimates of slot #1 for each port */
-  chest_ce_sf(&q->chest, q->sf_symbols, q->ce, 0);
-  
-  if (q->pbch_last_trial && 
-    (q->frame_total_cnt - q->pbch_last_trial > 2)) 
-  {
-    pbch_decode_reset(&q->pbch);
-    INFO("Resetting PBCH decoder: last trial %d, now is %d\n", 
-         q->pbch_last_trial, q->frame_total_cnt);
-    q->pbch_last_trial = 0;
-  }
-  
-  if (pbch_decode(&q->pbch, q->sf_symbols, q->ce, &q->mib) == 1) {        
-    q->frame_number = q->mib.sfn; 
-    q->cell.nof_ports = q->mib.nof_ports;
-    q->cell.nof_prb = q->mib.nof_prb;
-    
-    if (!q->pbch_decoded) {
-      printf("\n\nMIB decoded:\n");
-      pbch_mib_fprint(stdout, &q->mib, q->cell.id);
-      if (q->change_srate) {
-        ret = update_srate(q);        
-      }
-    } else { 
-      INFO("MIB decoded #%d SFN: %d\n", q->pbch_decoded, q->mib.sfn);
-    }
-    q->pbch_decoded++;
-    
-    pbch_decode_reset(&q->pbch);
-
-  } else {
-    INFO("MIB not decoded: %d\n", q->frame_total_cnt/2);
-    q->pbch_last_trial = q->frame_total_cnt;
-  }
-  
-  return ret; 
-}
-
-static int find_peak_ok(ue_sync_t *q) {
-  int ret; 
-  
-  if (q->peak_idx < CURRENT_SFLEN) {
-    /* Receive the rest of the next subframe */
-    if (q->recv_callback(q->stream, &q->input_buffer[CURRENT_SFLEN], q->peak_idx+CURRENT_SFLEN/2) < 0) {
-      return LIBLTE_ERROR;
-    }
-  }
-  
-  if (sync_sss_detected(&q->s)) {
-    ret = sync_get_cell_id(&q->s);
-    if (ret >= 0) {
-      q->cell.id = (uint32_t) ret;
-      q->cell.cp = sync_get_cp(&q->s);
-    }
-    
-    /* Get the subframe index (0 or 5) */
-    q->sf_idx = sync_get_slot_id(&q->s)/2;
-   
-    /* Reset variables */ 
-    q->frame_ok_cnt = 0;
-    q->frame_no_cnt = 0;
-    q->frame_total_cnt = 0;       
-
-    /* Goto Tracking state */
-    q->state = SF_TRACK;      
-    ret = LIBLTE_SUCCESS;
-  
-    INFO("Found peak at %d, value %.3f, SF_idx: %d, Cell_id: %d CP: %s\n", 
-        q->peak_idx, sync_get_peak_value(&q->s), q->sf_idx, q->cell.id, lte_cp_string(q->cell.cp));       
-    
-    if (q->peak_idx < CURRENT_SFLEN) {
-      q->sf_idx++;
-    }
-    
-    return ret;
-  } else {
-    INFO("Found peak at %d, SSS not detected\n", q->peak_idx);
-    return 0;
-  }
-}
-
-int track_peak_ok(ue_sync_t *q, uint32_t track_idx) {
-  int ret = LIBLTE_SUCCESS; 
-  
-   /* Make sure subframe idx is what we expect */
-  if ((q->sf_idx != sync_get_slot_id(&q->s)/2) && q->decode_sss_on_track) {
-    INFO("\nWarning: Expected SF idx %d but got %d!\n", 
-          q->sf_idx, sync_get_slot_id(&q->s)/2);
-    q->sf_idx = sync_get_slot_id(&q->s)/2;
-  } else {
-    q->time_offset = ((int) track_idx - (int) CURRENT_FFTSIZE); 
-
-    /* If the PSS peak is beyond the frame (we sample too slowly), 
-      discard the offseted samples to align next frame */
-    if (q->time_offset > 0 && q->time_offset < MAX_TIME_OFFSET) {
-      ret = q->recv_callback(q->stream, dummy, (uint32_t) q->time_offset);        
-    } else {
-      ret = LIBLTE_SUCCESS;
-    }
-    
-    /* compute cumulative moving average CFO */
-    q->cur_cfo = EXPAVERAGE(sync_get_cfo(&q->s), q->cur_cfo, q->frame_ok_cnt);
-    
-    /* compute cumulative moving average time offset */
-    q->mean_time_offset = (float) EXPAVERAGE((float) q->time_offset, q->mean_time_offset, q->frame_ok_cnt);
-
-    q->peak_idx = CURRENT_SFLEN/2 + q->time_offset;  
-    q->frame_ok_cnt++;
-    q->frame_no_cnt = 0;
-    
-    
-    if (ret >= LIBLTE_SUCCESS) {
-      ret = LIBLTE_SUCCESS; 
-    }
-  }
-  
-  return ret;
-}
-
-int track_peak_no(ue_sync_t *q) {
-  
-  /* if we missed too many PSS go back to FIND */
-  q->frame_no_cnt++; 
-  if (q->frame_no_cnt >= TRACK_MAX_LOST) {
-    printf("\n%d frames lost. Going back to FIND\n", (int) q->frame_no_cnt);
-    q->state = SF_FIND;
-  } else {
-    INFO("Tracking peak not found. Peak %.3f, %d lost\n", sync_get_peak_value(&q->s), (int) q->frame_no_cnt);    
-  }
-
-  return LIBLTE_SUCCESS;
-}
-
-static int receive_samples(ue_sync_t *q) {
-  
-  if (q->cell.nof_prb >= 6 && q->cell.nof_prb <= 100) {
-    /* A negative time offset means there are samples in our buffer for the next subframe, 
-    because we are sampling too fast. 
-    */
-    if (q->time_offset < 0) {
-      q->time_offset = -q->time_offset;
-    } 
-    /* copy last part of the last subframe (use move since there could be overlapping) */
-    memcpy(q->receive_buffer, &q->input_buffer[CURRENT_SFLEN-q->time_offset], q->time_offset*sizeof(cf_t));
-
-    /* Get 1 subframe from the USRP getting more samples and keeping the previous samples, if any */  
-    if (q->recv_callback(q->stream, &q->receive_buffer[q->time_offset], CURRENT_SFLEN - q->time_offset) < 0) {
-      return LIBLTE_ERROR;
-    }
-    
-    /* reset time offset */
-    q->time_offset = 0;
-
-    return LIBLTE_SUCCESS; 
-  } else {
-    return LIBLTE_ERROR_INVALID_INPUTS;
-  }
-}
-
-int ue_sync_get_buffer(ue_sync_t *q, cf_t **sf_symbols) {
-  int ret = LIBLTE_ERROR_INVALID_INPUTS; 
-  uint32_t track_idx; 
-  struct timeval t[3];
-
-  if (q               != NULL   &&
-      sf_symbols      != NULL   &&
-      q->input_buffer != NULL)
-  {
-    
-    if (receive_samples(q)) {
-      fprintf(stderr, "Error receiving samples\n");
-      return -1;
-    }
-    
-    agc_process(&q->agc, q->receive_buffer, q->input_buffer, CURRENT_SFLEN);
-    
-    switch (q->state) {
-      case SF_AGC: 
-        q->frame_total_cnt++;
-        if (q->frame_total_cnt >= AGC_NOF_FRAMES) {
-          q->state = SF_FIND; 
-          q->frame_total_cnt = 0; 
-        }
-        ret = 0;
-        break;
-      case SF_FIND:
-        q->s.sss_en = true; 
-        
-        /* Find peak and cell id */
-        ret = sync_find(&q->s, q->input_buffer, &q->peak_idx);
-        if (ret < 0) {
-          fprintf(stderr, "Error finding correlation peak (%d)\n", ret);
-          return -1;
-        }
-        
-        DEBUG("Find PAR=%.2f\n", sync_get_peak_value(&q->s));
-        
-        if (ret == 1) {
-          ret = find_peak_ok(q);
-          /* Initialize PBCH decoder */
-          if (ret == LIBLTE_SUCCESS) {
-            if (!q->pbch_initialized && q->pbch_decoder_enabled) {
-              ret = mib_decoder_initialize(q);
-              if (ret < 0) {
-                fprintf(stderr, "Error initializing MIB decoder\n");
-              }
-            }
-          } else if (ret < 0) {
-            if (ret < 0) {
-              fprintf(stderr, "Error processing find peak \n");
-            }
-          }
-        } else if (q->peak_idx != 0) {
-          uint32_t rlen; 
-          if (q->peak_idx < CURRENT_SFLEN/2) {
-            rlen = CURRENT_SFLEN/2-q->peak_idx;
-          } else {
-            rlen = q->peak_idx;
-          }
-          if (q->recv_callback(q->stream, q->receive_buffer, rlen) < 0) {
-            return LIBLTE_ERROR;
-          }
-        }
-      break;
-      case SF_TRACK:
-        ret = LIBLTE_SUCCESS;
-        
-        q->s.sss_en = q->decode_sss_on_track; 
-        
-        q->sf_idx = (q->sf_idx + 1) % 10;
-
-        DEBUG("TRACK: SF=%d FrameCNT: %d\n", q->sf_idx, q->frame_total_cnt);
-        
-        /* Every SF idx 0 and 5, find peak around known position q->peak_idx */
-        if (q->sf_idx == 0 || q->sf_idx == 5) {
-
-          #ifdef MEASURE_EXEC_TIME
-          gettimeofday(&t[1], NULL);
-          #endif
-          
-          track_idx = 0; 
-          
-          /* track pss around the middle of the subframe, where the PSS is */
-          ret = sync_track(&q->s, q->input_buffer, CURRENT_SFLEN/2-CURRENT_FFTSIZE, &track_idx);
-          if (ret < 0) {
-            fprintf(stderr, "Error tracking correlation peak\n");
-            return -1;
-          }
-          
-          #ifdef MEASURE_EXEC_TIME
-          gettimeofday(&t[2], NULL);
-          get_time_interval(t);
-          q->mean_exec_time = (float) EXPAVERAGE((float) t[0].tv_usec, q->mean_exec_time, q->frame_total_cnt);
-          #endif
-
-          if (ret == 1) {
-            ret = track_peak_ok(q, track_idx);
-          } else {
-            ret = track_peak_no(q); 
-          }
-          
-          INFO("TRACK %3d: Value=%.3f SF=%d Track_idx=%d Offset=%d CFO: %f\n", 
-                (int) q->frame_total_cnt, sync_get_peak_value(&q->s), q->sf_idx, track_idx, q->time_offset, sync_get_cfo(&q->s));
-          
-          q->frame_total_cnt++; 
-          
-          if (ret == LIBLTE_ERROR) {
-            fprintf(stderr, "Error processing tracking peak\n");
-            q->state = SF_FIND; 
-            return LIBLTE_SUCCESS;
-          } 
-        }
-        
-        /* Do CFO Correction and deliver the frame */
-        cfo_correct(&q->cfocorr, q->input_buffer, q->input_buffer, -q->cur_cfo / CURRENT_FFTSIZE);         
-        *sf_symbols = q->input_buffer;
-        
-        /* At subframe 0, try to decode PBCH if not yet decoded */
-        if (q->sf_idx == 0) {
-          if(q->pbch_decoder_enabled                     &&
-            (q->pbch_decoded < q->nof_mib_decodes || q->pbch_decode_always)) 
-          {
-            mib_decoder_run(q);
-          } else {
-            q->mib.sfn = (q->mib.sfn + 1) % 1024;
-          }
-        }
-
-        if (ret == LIBLTE_SUCCESS) {
-          if (q->pbch_decoder_enabled) {
-            if (q->pbch_decoded >= q->nof_mib_decodes) {
-              ret = 1; 
-            } else {
-              ret = 0;
-            }
-          } else {
-            ret = 1;
-          }
-        }
-      break;
-    }
-  }  
-  DEBUG("UE SYNC returns %d\n", ret);
-  return ret; 
-}
-
-void ue_sync_reset(ue_sync_t *q) {
-  q->state = SF_AGC;
-    
-  q->pbch_last_trial = 0; 
-  q->frame_ok_cnt = 0;
-  q->frame_no_cnt = 0;
-  q->frame_total_cnt = 0; 
-  q->cur_cfo = 0;
-  q->mean_time_offset = 0;
-  q->time_offset = 0;
-  #ifdef MEASURE_EXEC_TIME
-  q->mean_exec_time = 0;
-  #endif
-  
-  pbch_decode_reset(&q->pbch);
-}
-

lte/phy/lib/phch/test/CMakeLists.txt

@@ -19,23 +19,6 @@
 # and at http://www.gnu.org/licenses/.
 #
 
-########################################################################
-# UE SYNC TEST (Only compiled if CUHD is available)
-########################################################################
-LIST(FIND OPTIONAL_LIBS cuhd CUHD_FIND)
-LIST(FIND OPTIONAL_LIBS graphics GRAPHICS_FIND)
-IF(${CUHD_FIND} GREATER -1)
-  ADD_EXECUTABLE(ue_sync_usrp ue_sync_usrp.c)
-  TARGET_LINK_LIBRARIES(ue_sync_usrp lte_phy cuhd)
-ENDIF(${CUHD_FIND} GREATER -1)
-
-IF(${GRAPHICS_FIND} EQUAL -1)
-  SET_TARGET_PROPERTIES(ue_sync_usrp PROPERTIES COMPILE_DEFINITIONS "DISABLE_GRAPHICS")
-ELSE(${GRAPHICS_FIND} EQUAL -1)
-  target_link_libraries(ue_sync_usrp graphics)
-ENDIF(${GRAPHICS_FIND} EQUAL -1)
-
-
 ########################################################################
 # PBCH TEST  
 ########################################################################

lte/phy/lib/phch/test/pbch_file_test.c

@@ -117,14 +117,14 @@ int base_init() {
     exit(-1);
   }
 
-  fft_buffer = malloc(2 * CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB * sizeof(cf_t));
+  fft_buffer = malloc(SLOT_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
   if (!fft_buffer) {
     perror("malloc");
     return -1;
   }
 
   for (i=0;i<cell.nof_ports;i++) {
-    ce[i] = malloc(2 * CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB * sizeof(cf_t));
+    ce[i] = malloc(SLOT_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
     if (!ce[i]) {
       perror("malloc");
       return -1;
@@ -194,7 +194,7 @@ int main(int argc, char **argv) {
 
   n = filesource_read(&fsrc, input_buffer, FLEN);
 
-  lte_fft_run_sf(&fft, input_buffer, fft_buffer);
+  lte_fft_run_slot(&fft, &input_buffer[960], fft_buffer);
 
   if (fmatlab) {
     fprintf(fmatlab, "outfft=");
@@ -205,7 +205,7 @@ int main(int argc, char **argv) {
   }
 
   /* Get channel estimates for each port */
-  chest_ce_sf(&chest, fft_buffer, ce, 0);
+  chest_ce_slot(&chest, fft_buffer, ce, 1);
 
   INFO("Decoding PBCH\n", 0);
 

lte/phy/lib/phch/test/pbch_test.c

@@ -78,11 +78,11 @@ int main(int argc, char **argv) {
   int i, j;
   cf_t *ce[MAX_PORTS];
   int nof_re;
-  cf_t *sf_symbols[MAX_PORTS];
+  cf_t *slot1_symbols[MAX_PORTS];
 
   parse_args(argc,argv);
 
-  nof_re = 2 * CPNORM_NSYMB * cell.nof_prb * RE_X_RB;
+  nof_re = SLOT_LEN_RE(cell.nof_prb, CPNORM); 
 
   /* init memory */
   for (i=0;i<cell.nof_ports;i++) {
@@ -94,8 +94,8 @@ int main(int argc, char **argv) {
     for (j=0;j<nof_re;j++) {
       ce[i][j] = 1;
     }
-    sf_symbols[i] = malloc(sizeof(cf_t) * nof_re);
+    slot1_symbols[i] = malloc(sizeof(cf_t) * nof_re);
-    if (!sf_symbols[i]) {
+    if (!slot1_symbols[i]) {
       perror("malloc");
       exit(-1);
     }
@@ -112,17 +112,17 @@ int main(int argc, char **argv) {
   mib_tx.phich_resources = R_1_6;
   mib_tx.sfn = 124;
 
-  pbch_encode(&pbch, &mib_tx, sf_symbols);
+  pbch_encode(&pbch, &mib_tx, slot1_symbols);
 
   /* combine outputs */
   for (i=1;i<cell.nof_ports;i++) {
     for (j=0;j<nof_re;j++) {
-      sf_symbols[0][j] += sf_symbols[i][j];
+      slot1_symbols[0][j] += slot1_symbols[i][j];
     }
   }
 
   pbch_decode_reset(&pbch);
-  if (1 != pbch_decode(&pbch, sf_symbols[0], ce, &mib_rx)) {
+  if (1 != pbch_decode(&pbch, slot1_symbols[0], ce, &mib_rx)) {
     printf("Error decoding\n");
     exit(-1);
   }
@@ -131,7 +131,7 @@ int main(int argc, char **argv) {
 
   for (i=0;i<cell.nof_ports;i++) {
     free(ce[i]);
-    free(sf_symbols[i]);
+    free(slot1_symbols[i]);
   }
 
   if (!memcmp(&mib_tx, &mib_rx, sizeof(pbch_mib_t))) {

lte/phy/lib/phch/test/pcfich_file_test.c

@@ -119,7 +119,7 @@ int base_init() {
     fmatlab = NULL;
   }
 
-  flen = SLOT_LEN(lte_symbol_sz(cell.nof_prb), cell.cp);
+  flen = SLOT_LEN(lte_symbol_sz(cell.nof_prb));
 
   input_buffer = malloc(flen * sizeof(cf_t));
   if (!input_buffer) {

lte/phy/lib/phch/test/pdcch_file_test.c

@@ -133,7 +133,7 @@ int base_init() {
     fmatlab = NULL;
   }
 
-  flen = 2 * (SLOT_LEN(lte_symbol_sz(cell.nof_prb), cell.cp));
+  flen = 2 * (SLOT_LEN(lte_symbol_sz(cell.nof_prb)));
 
   input_buffer = malloc(flen * sizeof(cf_t));
   if (!input_buffer) {

lte/phy/lib/phch/test/pdsch_file_test.c

@@ -136,7 +136,7 @@ int base_init() {
     fmatlab = NULL;
   }
 
-  flen = 2 * (SLOT_LEN(lte_symbol_sz(cell.nof_prb), cell.cp));
+  flen = 2 * (SLOT_LEN(lte_symbol_sz(cell.nof_prb)));
 
   input_buffer = malloc(flen * sizeof(cf_t));
   if (!input_buffer) {

lte/phy/lib/phch/test/phich_file_test.c

@@ -144,7 +144,7 @@ int base_init() {
     fmatlab = NULL;
   }
 
-  flen = SLOT_LEN(lte_symbol_sz(cell.nof_prb), cell.cp);
+  flen = SLOT_LEN(lte_symbol_sz(cell.nof_prb));
 
   input_buffer = malloc(flen * sizeof(cf_t));
   if (!input_buffer) {

lte/phy/lib/sync/src/pss.c

@@ -36,6 +36,7 @@
 #include "liblte/phy/utils/dft.h"
 #include "liblte/phy/utils/vector.h"
 #include "liblte/phy/utils/convolution.h"
+#include "liblte/phy/utils/debug.h"
 
 
 int pss_synch_init_N_id_2(cf_t *pss_signal_freq, uint32_t N_id_2, uint32_t fft_size) {
@@ -45,7 +46,7 @@ int pss_synch_init_N_id_2(cf_t *pss_signal_freq, uint32_t N_id_2, uint32_t fft_s
   int ret = LIBLTE_ERROR_INVALID_INPUTS;
   
   if (lte_N_id_2_isvalid(N_id_2)    && 
-      fft_size                  < 2048) 
+      fft_size                  <= 2048) 
   {
     
     pss_generate(pss_signal_time, N_id_2);
@@ -60,10 +61,11 @@ int pss_synch_init_N_id_2(cf_t *pss_signal_freq, uint32_t N_id_2, uint32_t fft_s
     
     dft_plan_set_mirror(&plan, true);
     dft_plan_set_dc(&plan, true);
+    dft_plan_set_norm(&plan, true);
     dft_run_c(&plan, pss_signal_pad, pss_signal_freq);
 
-    vec_sc_prod_cfc(pss_signal_freq, (float) 1 / (fft_size), pss_signal_pad, fft_size);
+    vec_conj_cc(pss_signal_freq, pss_signal_freq, fft_size);
-    vec_conj_cc(pss_signal_pad, pss_signal_freq, fft_size);
+    vec_sc_prod_cfc(pss_signal_freq, 1.0/62.0, pss_signal_freq, fft_size);
 
     dft_plan_free(&plan);
     
@@ -97,11 +99,6 @@ int pss_synch_init_fft(pss_synch_t *q, uint32_t frame_size, uint32_t fft_size) {
     
     buffer_size = fft_size + frame_size + 1;
     
-    q->conv_abs = vec_malloc(buffer_size * sizeof(float));
-    if (!q->conv_abs) {
-      fprintf(stderr, "Error allocating memory\n");
-      goto clean_and_exit;
-    }
     q->tmp_input = vec_malloc(buffer_size * sizeof(cf_t));
     if (!q->tmp_input) {
       fprintf(stderr, "Error allocating memory\n");
@@ -160,9 +157,6 @@ void pss_synch_free(pss_synch_t *q) {
     if (q->conv_output) {
       free(q->conv_output);
     }
-    if (q->conv_abs) {
-      free(q->conv_abs);
-    }
 
     bzero(q, sizeof(pss_synch_t));    
   }
@@ -231,8 +225,7 @@ int pss_synch_set_N_id_2(pss_synch_t *q, uint32_t N_id_2) {
  *
  * Input buffer must be subframe_size long.
  */
-int pss_synch_find_pss(pss_synch_t *q, cf_t *input, 
+int pss_synch_find_pss(pss_synch_t *q, cf_t *input, float *corr_peak_value) 
-                       float *corr_peak_value, float *corr_mean_value) 
 {
   int ret = LIBLTE_ERROR_INVALID_INPUTS;
   
@@ -252,6 +245,7 @@ int pss_synch_find_pss(pss_synch_t *q, cf_t *input,
     memcpy(q->tmp_input, input, q->frame_size * sizeof(cf_t));
     bzero(&q->tmp_input[q->frame_size], q->fft_size * sizeof(cf_t));
 
+    /* Correlate input with PSS sequence */
   #ifdef CONVOLUTION_FFT
     conv_output_len = conv_fft_cc_run(&q->conv_fft, q->tmp_input,
         q->pss_signal_freq[q->N_id_2], q->conv_output);
@@ -259,16 +253,11 @@ int pss_synch_find_pss(pss_synch_t *q, cf_t *input,
     conv_output_len = conv_cc(input, q->pss_signal_freq[q->N_id_2], q->conv_output, q->frame_size, q->fft_size);
   #endif
 
-    vec_abs_cf(q->conv_output, q->conv_abs, conv_output_len);
+    /* Find maximum of the absolute value of the correlation */
-    corr_peak_pos = vec_max_fi(q->conv_abs, conv_output_len);
+    corr_peak_pos = vec_max_abs_ci(q->conv_output, conv_output_len);
     if (corr_peak_value) {
-      *corr_peak_value = q->conv_abs[corr_peak_pos];
+      *corr_peak_value = cabsf(q->conv_output[corr_peak_pos]);
-    }
-    if (corr_mean_value) {
-      *corr_mean_value = vec_acc_ff(q->conv_abs, conv_output_len)
-          / conv_output_len;
     }
-
     ret = (int) corr_peak_pos;          
   } 
   return ret;

lte/phy/lib/sync/src/sss.c

@@ -44,7 +44,7 @@ void generate_N_id_1_table(uint32_t table[30][30]);
 int sss_synch_init(sss_synch_t *q, uint32_t fft_size) {
   
   if (q                 != NULL  &&
-      fft_size          < 2048)
+      fft_size          <= 2048)
   {
     uint32_t N_id_2;
     struct sss_tables sss_tables;
@@ -73,7 +73,7 @@ int sss_synch_init(sss_synch_t *q, uint32_t fft_size) {
 
 int sss_synch_realloc(sss_synch_t *q, uint32_t fft_size) {
   if (q                 != NULL  &&
-      fft_size          < 2048)
+      fft_size          <= 2048)
   {
     dft_plan_free(&q->dftp_input);
     if (dft_plan(&q->dftp_input, fft_size, FORWARD, COMPLEX)) {

lte/phy/lib/sync/src/sync.c

@@ -26,6 +26,8 @@
  */
 
 #include <strings.h>
+#include <complex.h>
+#include <math.h>
 
 #include "liblte/phy/utils/debug.h"
 #include "liblte/phy/common/phy_common.h"
@@ -41,25 +43,25 @@ static bool fft_size_isvalid(uint32_t fft_size) {
   }
 }
 
-int sync_init(sync_t *q, uint32_t find_frame_size, uint32_t track_frame_size, uint32_t fft_size) {
+int sync_init(sync_t *q, uint32_t frame_size, uint32_t fft_size) {
 
   int ret = LIBLTE_ERROR_INVALID_INPUTS; 
   
   if (q                 != NULL         &&
-      find_frame_size   > fft_size &&
+      frame_size        >= fft_size     &&
-      find_frame_size   < 307200        &&
+      frame_size        <= 307200       &&
       fft_size_isvalid(fft_size))
   {
     bzero(q, sizeof(sync_t));
-    q->pss_mode = PEAK_MEAN;
     q->detect_cp = true;
+    q->normalize_en = true; 
     q->sss_en = true;
     q->N_id_2 = 1000; 
     q->N_id_1 = 1000;
     q->fft_size = fft_size;
-    q->find_frame_size = find_frame_size;
+    q->frame_size = frame_size;
     
-    if (pss_synch_init_fft(&q->pss_find, find_frame_size, fft_size)) {
+    if (pss_synch_init_fft(&q->pss, frame_size, fft_size)) {
       fprintf(stderr, "Error initializing PSS object\n");
       return LIBLTE_ERROR;
     }
@@ -67,119 +69,74 @@ int sync_init(sync_t *q, uint32_t find_frame_size, uint32_t track_frame_size, ui
       fprintf(stderr, "Error initializing SSS object\n");
       return LIBLTE_ERROR;
     }
-    if (pss_synch_init_fft(&q->pss_track, track_frame_size, fft_size)) {
-      fprintf(stderr, "Error initializing PSS track object\n");
-      return LIBLTE_ERROR;
-    }      
-
-    DEBUG("SYNC init with find_frame_size=%d and fft_size=%d\n", find_frame_size, fft_size);
-    
-    ret = LIBLTE_SUCCESS;
-  }  
-  return ret;
-}
-
-int sync_realloc(sync_t *q, uint32_t find_frame_size, uint32_t track_frame_size, 
-                 uint32_t fft_size)
-{
-  int ret = LIBLTE_ERROR_INVALID_INPUTS; 
-  
-  if (q                 != NULL         &&
-      find_frame_size   > fft_size &&
-      find_frame_size   < 307200        &&
-      fft_size_isvalid(fft_size))
-  {
-    q->N_id_2 = 1000; 
-    q->N_id_1 = 1000;
-    q->fft_size = fft_size;
-    q->find_frame_size = find_frame_size;
 
-    pss_synch_free(&q->pss_find);
+    DEBUG("SYNC init with frame_size=%d and fft_size=%d\n", frame_size, fft_size);
-    if (pss_synch_init_fft(&q->pss_find, find_frame_size, fft_size)) {
-      fprintf(stderr, "Error initializing PSS object\n");
-      return LIBLTE_ERROR;
-    }
-   
-    pss_synch_free(&q->pss_track);      
-    if (pss_synch_init_fft(&q->pss_track, track_frame_size, fft_size)) {
-      fprintf(stderr, "Error initializing PSS track object\n");
-      return LIBLTE_ERROR;
-    }
-    
-    if (sss_synch_realloc(&q->sss, fft_size)) {
-      fprintf(stderr, "Error realloc'ing SSS object\n");
-      return LIBLTE_ERROR;
-    }
-
-    DEBUG("SYNC init with find_frame_size=%d and fft_size=%d\n", find_frame_size, fft_size);
     
     ret = LIBLTE_SUCCESS;
+  }  else {
+    fprintf(stderr, "Invalid parameters frame_size: %d, fft_size: %d\n", frame_size, fft_size);
   }
   return ret;
 }
 
 void sync_free(sync_t *q) {
   if (q) {
-    pss_synch_free(&q->pss_track);      
+    pss_synch_free(&q->pss);     
-    pss_synch_free(&q->pss_find);
     sss_synch_free(&q->sss);  
   }
 }
 
-void sync_pss_det_absolute(sync_t *q) {
+void sync_set_threshold(sync_t *q, float threshold) {
-  q->pss_mode = ABSOLUTE;
+  q->threshold = threshold;
-}
-void sync_pss_det_peak_to_avg(sync_t *q) {
-  q->pss_mode = PEAK_MEAN;
-}
-
-void sync_set_threshold(sync_t *q, float find_threshold, float track_threshold) {
-  q->find_threshold = find_threshold;
-  q->track_threshold = track_threshold;
 }
 
 void sync_sss_en(sync_t *q, bool enabled) {
   q->sss_en = enabled;
 }
 
+void sync_normalize_en(sync_t *q, bool enable) {
+  q->normalize_en = enable; 
+}
+
 bool sync_sss_detected(sync_t *q) {
   return lte_N_id_1_isvalid(q->N_id_1);
 }
 
 int sync_get_cell_id(sync_t *q) {
-  if (q->N_id_2 != 10) {
   if (lte_N_id_2_isvalid(q->N_id_2) && lte_N_id_1_isvalid(q->N_id_1)) {
     return q->N_id_1*3 + q->N_id_2;      
   } else {
     fprintf(stderr, "Error getting cell_id, invalid N_id_1 or N_id_2\n");
     return LIBLTE_ERROR;
   }
-  } else {
-    fprintf(stderr, "Error getting cell_id, N_id_2 not set\n");
-    return LIBLTE_ERROR;
-  }
 }
 
-uint32_t sync_get_N_id_1(sync_t *q) {
+int sync_set_N_id_2(sync_t *q, uint32_t N_id_2) {
-  return q->N_id_1;
+  if (lte_N_id_2_isvalid(N_id_2)) {
+    q->N_id_2 = N_id_2;    
+    return LIBLTE_SUCCESS;
+  } else {
+    fprintf(stderr, "Invalid N_id_2=%d\n", N_id_2);
+    return LIBLTE_ERROR_INVALID_INPUTS;
   }
-
-uint32_t sync_get_N_id_2(sync_t *q) {
-  return q->N_id_2;
 }
 
-uint32_t sync_get_slot_id(sync_t *q) {
+uint32_t sync_get_sf_idx(sync_t *q) {
-  return q->slot_id;
+  return q->sf_idx;
 }
 
 float sync_get_cfo(sync_t *q) {
   return q->cfo;
 }
 
-float sync_get_peak_value(sync_t *q) {
+float sync_get_last_peak_value(sync_t *q) {
   return q->peak_value;
 }
 
+float sync_get_peak_value(sync_t *q) {
+  return q->mean_peak_value;
+}
+
 void sync_cp_en(sync_t *q, bool enabled) {
   q->detect_cp = enabled;
 }
@@ -188,129 +145,134 @@ lte_cp_t sync_get_cp(sync_t *q) {
   return q->cp;
 }
 
-int sync_sss(sync_t *q, cf_t *input, uint32_t peak_pos, bool en_cp) {
+/* CP detection algorithm taken from: 
-  uint32_t m0, m1;
+ * "SSS Detection Method for Initial Cell Search in 3GPP LTE FDD/TDD Dual Mode Receiver"
-  int sss_idx_n, sss_idx_e, ret;
+ * by Jung-In Kim et al. 
-  float m0_value_e, m1_value_e,m0_value_n, m1_value_n;
+ */
-  uint32_t slot_id_e, N_id_1_e, slot_id_n, N_id_1_n;
+static lte_cp_t detect_cp(sync_t *q, cf_t *input, uint32_t peak_pos) 
-
+{
-  sss_synch_set_N_id_2(&q->sss, q->N_id_2);
+  float R_norm, R_ext, C_norm, C_ext; 
-      
+  float M_norm, M_ext; 
-  /* Make sure we have enough room to find SSS sequence */
+  
-  sss_idx_n = (int) peak_pos - 2*(q->fft_size + CP(q->fft_size, CPNORM_LEN));
+  R_norm = crealf(vec_dot_prod_conj_ccc(&input[peak_pos-q->fft_size-CP_NORM(7, q->fft_size)], 
-  sss_idx_e = (int) peak_pos - 2*(q->fft_size + CP(q->fft_size, CPEXT_LEN));
+                                        &input[peak_pos-CP_NORM(7, q->fft_size)], 
-
+                                        CP_NORM(7, q->fft_size)));    
-  if (en_cp) {
+  C_norm = cabsf(vec_dot_prod_conj_ccc(&input[peak_pos-q->fft_size-CP_NORM(7, q->fft_size)], 
-    if (sss_idx_n < 0 || sss_idx_e < 0) {
+                                       &input[peak_pos-q->fft_size-CP_NORM(7, q->fft_size)], 
-      INFO("Not enough room to decode SSS (%d, %d)\n", sss_idx_n, sss_idx_e);
+                                       CP_NORM(7, q->fft_size)));
-      return LIBLTE_SUCCESS;
+  R_ext  = crealf(vec_dot_prod_conj_ccc(&input[peak_pos-q->fft_size-CP_EXT(q->fft_size)], 
-    }
+                                        &input[peak_pos-CP_EXT(q->fft_size)], 
+                                        CP_EXT(q->fft_size)));
+  C_ext  = cabsf(vec_dot_prod_conj_ccc(&input[peak_pos-q->fft_size-CP_EXT(q->fft_size)], 
+                                       &input[peak_pos-q->fft_size-CP_EXT(q->fft_size)], 
+                                       CP_EXT(q->fft_size)));
+  M_norm = R_norm/C_norm;
+  M_ext = R_ext/C_ext;
+
+  if (M_norm > M_ext) {
+    return CPNORM;    
+  } else if (M_norm < M_ext) {
+    return CPEXT;
   } else {
-    if (CP_ISNORM(q->cp)) {
+    if (R_norm > R_ext) {
-      if (sss_idx_n < 0) {
+      return CPNORM;
-        INFO("Not enough room to decode normal CP SSS (sss_idx=%d, peak_pos=%d)\n", sss_idx_n, peak_pos);
-        return LIBLTE_SUCCESS;
-      }
     } else {
-      if (sss_idx_e < 0) {
+      return CPEXT;
-        INFO("Not enough room to decode extended CP SSS (sss_idx=%d, peak_pos=%d)\n", sss_idx_e, peak_pos);
-        return LIBLTE_SUCCESS;
     }
   }
 }
 
-  slot_id_n = 0;
+int sync_sss(sync_t *q, cf_t *input, uint32_t peak_pos) {
-  slot_id_e = 0;
+  uint32_t m0, m1;
-  N_id_1_n = 0;
+  int sss_idx, ret;
-  N_id_1_e = 0;
+  float m0_value, m1_value;
 
-  /* try Normal CP length */
+  sss_synch_set_N_id_2(&q->sss, q->N_id_2);
-  if (en_cp || CP_ISNORM(q->cp)) {
-    sss_synch_m0m1(&q->sss, &input[sss_idx_n], &m0, &m0_value_n, &m1, &m1_value_n);
 
-    slot_id_n = 2 * sss_synch_subframe(m0, m1);
+  if (q->detect_cp) {
-    ret = sss_synch_N_id_1(&q->sss, m0, m1);
+    q->cp = detect_cp(q, input, peak_pos);
-    if (ret >= 0) {
-      N_id_1_n = (uint32_t) ret;
-    } else {
-      N_id_1_n = 1000;
   }
+  
+  /* Make sure we have enough room to find SSS sequence */
+  sss_idx = (int) peak_pos - 2*(q->fft_size + CP(q->fft_size, q->cp));
+
+  if (sss_idx < 0) {
+    INFO("Not enough room to decode CP SSS (sss_idx=%d, peak_pos=%d)\n", sss_idx, peak_pos);
+    return LIBLTE_SUCCESS;
   }
       
-  if (en_cp || CP_ISEXT(q->cp)) {
+  /* try Normal CP length */
-    /* Now try Extended CP length */
+  sss_synch_m0m1(&q->sss, &input[sss_idx], &m0, &m0_value, &m1, &m1_value);
-    sss_synch_m0m1(&q->sss, &input[sss_idx_e], &m0, &m0_value_e, &m1, &m1_value_e);
 
-    slot_id_e = 2 * sss_synch_subframe(m0, m1);
+  q->sf_idx = sss_synch_subframe(m0, m1);
   ret = sss_synch_N_id_1(&q->sss, m0, m1);
   if (ret >= 0) {
-      N_id_1_e = (uint32_t) ret;
+    q->N_id_1 = (uint32_t) ret;
   } else {
-      N_id_1_e = 1000;
+    q->N_id_1 = 1000;
-    }
-  }
-  
-  /* Correlation with extended CP hypoteshis is greater than with normal? */
-  if ((en_cp && m0_value_e * m1_value_e > m0_value_n * m1_value_n)
-      || CP_ISEXT(q->cp)) {
-    q->cp = CPEXT;
-    q->slot_id = slot_id_e;
-    q->N_id_1 = N_id_1_e;
-  /* otherwise is normal CP */
-  } else {
-    q->cp = CPNORM;
-    q->slot_id = slot_id_n;
-    q->N_id_1 = N_id_1_n;
   }
     
-  DEBUG("SSS detected N_id_1=%d, slot_idx=%d, position=%d/%d %s CP\n",
+  DEBUG("SSS detected N_id_1=%d, sf_idx=%d, %s CP\n",
-    q->N_id_1, q->slot_id, sss_idx_n, sss_idx_e, CP_ISNORM(q->cp)?"Normal":"Extended");
+    q->N_id_1, q->sf_idx, CP_ISNORM(q->cp)?"Normal":"Extended");
 
   return 1;
 }
 
-int sync_track(sync_t *q, cf_t *input, uint32_t offset, uint32_t *peak_position) {
+int sync_find(sync_t *q, cf_t *input, uint32_t find_offset, uint32_t *peak_position) 
+{
   
   int ret = LIBLTE_ERROR_INVALID_INPUTS; 
   
+  float peak_unnormalized, energy;
+  
   if (q                 != NULL     &&
       input             != NULL     &&
+      lte_N_id_2_isvalid(q->N_id_2) && 
       fft_size_isvalid(q->fft_size))
   {
-    float peak_value, mean_value, *mean_ptr;
     uint32_t peak_pos;
     
-    pss_synch_set_N_id_2(&q->pss_track, q->N_id_2);
+    if (peak_position) {
-    
+      *peak_position = 0; 
-    if (q->pss_mode == ABSOLUTE) {
-      mean_ptr = NULL;
-    } else {
-      mean_ptr = &mean_value;
     }
 
-    peak_pos = pss_synch_find_pss(&q->pss_track, &input[offset], &peak_value, mean_ptr);
+    pss_synch_set_N_id_2(&q->pss, q->N_id_2);
+  
+    peak_pos = pss_synch_find_pss(&q->pss, &input[find_offset], &peak_unnormalized);
     
-    if (q->pss_mode == ABSOLUTE) {
+    if (q->normalize_en        && 
-      q->peak_value = peak_value; 
+        peak_pos + find_offset >= q->fft_size) 
+    {
+      /* Compute the energy of the received PSS sequence to normalize */
+      cf_t *pss_ptr = &input[find_offset+peak_pos-q->fft_size];
+      energy = sqrtf(crealf(vec_dot_prod_conj_ccc(pss_ptr, pss_ptr, q->fft_size)) / (q->fft_size));
+      q->mean_energy = EXPAVERAGE(energy, q->mean_energy, q->frame_cnt);
     } else {     
-      q->peak_value = peak_value / mean_value;
+      if (q->mean_energy == 0.0) {
+        q->mean_energy = 1.0;
+      }
+      energy = q->mean_energy;
     }
 
-    DEBUG("PSS possible tracking peak pos=%d peak=%.2f threshold=%.2f\n",
+    /* Normalize and compute mean peak value */
-          peak_pos, peak_value, q->track_threshold);
+    q->peak_value = peak_unnormalized/energy;
+    q->mean_peak_value = EXPAVERAGE(q->peak_value, q->mean_peak_value, q->frame_cnt);
+    q->frame_cnt++;
     
-    if (q->peak_value           > q->track_threshold) {
+    /* If peak is over threshold, compute CFO and SSS */
-      if (offset + peak_pos       > q->fft_size) {
+    if (q->peak_value                  >= q->threshold) {
-        q->cfo = pss_synch_cfo_compute(&q->pss_track, &input[offset+peak_pos-q->fft_size]);
+      if (find_offset + peak_pos       >= q->fft_size) {
+        q->cfo = pss_synch_cfo_compute(&q->pss, &input[find_offset+peak_pos-q->fft_size]);
         if (q->sss_en) {
-          if (sync_sss(q, input, offset + peak_pos, false) < 0) {
+          if (sync_sss(q, input, find_offset + peak_pos) < 0) {
             fprintf(stderr, "Error synchronizing with SSS\n");
             return LIBLTE_ERROR;
           }
         } 
       } else {
-        printf("Warning: no space for CFO computation\n");
+        INFO("Warning: no space for CFO computation\n",0);
       }
+      
       if (peak_position) {
         *peak_position = peak_pos;
       }
@@ -318,81 +280,17 @@ int sync_track(sync_t *q, cf_t *input, uint32_t offset, uint32_t *peak_position)
     } else {
       ret = LIBLTE_SUCCESS;
     }
-  }
-  
-  return ret; 
-}
-
-int sync_find(sync_t *q, cf_t *input, uint32_t *peak_position) {
-  uint32_t N_id_2, peak_pos[3];
-  float peak_value[3];
-  float mean_value[3];
-  float max=-999;
-  uint32_t i;
-  int ret; 
-  float *mean_ptr; 
-  
-  for (N_id_2=0;N_id_2<3;N_id_2++) {
-     if (q->pss_mode == ABSOLUTE) {
-      mean_ptr = NULL;
-    } else {
-      mean_ptr = &mean_value[N_id_2];
-    }
-    pss_synch_set_N_id_2(&q->pss_find, N_id_2);
-    ret = pss_synch_find_pss(&q->pss_find, input, &peak_value[N_id_2], mean_ptr);
-    if (ret < 0) {
-      fprintf(stderr, "Error finding PSS for N_id_2=%d\n", N_id_2);
-      return LIBLTE_ERROR;
-    } 
-    peak_pos[N_id_2] = (uint32_t) ret;
-    
-  }
-  for (i=0;i<3;i++) {
-    if (peak_value[i] > max) {
-      max = peak_value[i];
-      N_id_2 = i;
-    }
-  }
-
-  if (q->pss_mode == ABSOLUTE) {
-    q->peak_value = peak_value[N_id_2];
-  } else {
-    q->peak_value = peak_value[N_id_2] / mean_value[N_id_2];
-  }
- 
-  if (peak_position) {
-    *peak_position = 0;
-  }
 
-  DEBUG("PSS possible peak N_id_2=%d, pos=%d peak=%.2f threshold=%.2f\n",
+    INFO("SYNC ret=%d N_id_2=%d pos=%d peak=%.2f energy=%.3f threshold=%.2f sf_idx=%d\n",
-      N_id_2, peak_pos[N_id_2], peak_value[N_id_2], q->find_threshold);
+          ret, q->N_id_2, peak_pos, q->peak_value, energy, q->threshold, q->sf_idx);
 
-  /* If peak detected */
+  } else if (lte_N_id_2_isvalid(q->N_id_2)) {
-  if (q->peak_value                   > q->find_threshold) {
+    fprintf(stderr, "Must call sync_set_N_id_2() first!\n");
-    if (peak_pos[N_id_2]                > q->fft_size             && 
-        peak_pos[N_id_2] + q->fft_size  < q->find_frame_size) 
-    {
-      q->N_id_2 = N_id_2;
-      pss_synch_set_N_id_2(&q->pss_find, q->N_id_2);
-      q->cfo = pss_synch_cfo_compute(&q->pss_find, &input[peak_pos[N_id_2]-q->fft_size]);
-      
-      DEBUG("PSS peak detected N_id_2=%d, pos=%d peak=%.2f par=%.2f th=%.2f cfo=%.4f\n", N_id_2,
-          peak_pos[N_id_2], peak_value[N_id_2], q->peak_value, q->find_threshold, q->cfo);
-
-      if (q->sss_en) {     
-        if (sync_sss(q, input, peak_pos[q->N_id_2], q->detect_cp) < 0) {
-          fprintf(stderr, "Error synchronizing with SSS\n");
-          return LIBLTE_ERROR;
-        }
-      }
   }
   
-    if (peak_position) {
+  return ret; 
-      *peak_position = peak_pos[N_id_2];
 }
 
-    return 1;
+void sync_reset(sync_t *q) {
-  } else {
+  q->frame_cnt = 0;
-    return LIBLTE_SUCCESS;
-  }
 }

lte/phy/lib/sync/test/CMakeLists.txt

@@ -19,6 +19,15 @@
 # and at http://www.gnu.org/licenses/.
 #
 
+########################################################################
+# PROGRAM TO DEBUG PSS FROM USRP  
+########################################################################
+
+LIST(FIND OPTIONAL_LIBS cuhd CUHD_FIND)
+IF(${CUHD_FIND} GREATER -1)
+  ADD_EXECUTABLE(pss_usrp pss_usrp.c)
+  TARGET_LINK_LIBRARIES(pss_usrp lte_phy cuhd)
+ENDIF(${CUHD_FIND} GREATER -1)
 
 ########################################################################
 # SYNC TEST  
@@ -27,10 +36,15 @@
 ADD_EXECUTABLE(sync_test sync_test.c)
 TARGET_LINK_LIBRARIES(sync_test lte_phy)
 
-ADD_TEST(sync_test_100 sync_test -o 100) 
+ADD_TEST(sync_test_100 sync_test -o 100 -c 501) 
-ADD_TEST(sync_test_400 sync_test -o 400) 
+ADD_TEST(sync_test_400 sync_test -o 400 -c 2) 
-ADD_TEST(sync_test_100_e sync_test -o 100 -e) 
+ADD_TEST(sync_test_100_e sync_test -o 100 -e -c 150) 
-ADD_TEST(sync_test_400_e sync_test -o 400 -e) 
+ADD_TEST(sync_test_400_e sync_test -o 400 -e -c 151) 
+
+ADD_TEST(sync_test_100 sync_test -o 100 -p 50 -c 501) 
+ADD_TEST(sync_test_400 sync_test -o 400 -p 50 -c 500) 
+ADD_TEST(sync_test_100_e sync_test -o 100 -e -p 50 -c 133) 
+ADD_TEST(sync_test_400_e sync_test -o 400 -e -p 50 -c 123) 
 
 ########################################################################
 # CFO TEST  

lte/phy/lib/sync/test/pss_usrp.c

@@ -0,0 +1,208 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <math.h>
+#include <time.h>
+
+#include <stdbool.h>
+
+#include "liblte/phy/phy.h"
+#include "liblte/cuhd/cuhd.h"
+
+uint32_t N_id_2 = 100;
+char *uhd_args="";
+float uhd_gain=40.0, uhd_freq=-1.0;
+int nof_frames = -1;
+uint32_t fft_size=64;
+float threshold = 0.4; 
+
+void usage(char *prog) {
+  printf("Usage: %s [agtvnp] -f rx_frequency_hz -i N_id_2\n", prog);
+  printf("\t-a UHD args [Default %s]\n", uhd_args);
+  printf("\t-g UHD Gain [Default %.2f dB]\n", uhd_gain);
+  printf("\t-n nof_frames [Default %d]\n", nof_frames);
+  printf("\t-s symbol_sz [Default %d]\n", fft_size);
+  printf("\t-t threshold [Default %.2f]\n", threshold);
+  printf("\t-v verbose\n");
+}
+
+void parse_args(int argc, char **argv) {
+  int opt;
+  while ((opt = getopt(argc, argv, "agtvsfi")) != -1) {
+    switch (opt) {
+    case 'a':
+      uhd_args = argv[optind];
+      break;
+    case 'g':
+      uhd_gain = atof(argv[optind]);
+      break;
+    case 'f':
+      uhd_freq = atof(argv[optind]);
+      break;
+    case 't':
+      threshold = atof(argv[optind]);
+      break;
+    case 'i':
+      N_id_2 = atoi(argv[optind]);
+      break;
+    case 's':
+      fft_size = atoi(argv[optind]);
+      break;
+    case 'n':
+      nof_frames = atoi(argv[optind]);
+      break;
+    case 'v':
+      verbose++;
+      break;
+    default:
+      usage(argv[0]);
+      exit(-1);
+    }
+  }
+  if (N_id_2 > 2 || uhd_freq < 0) {
+    usage(argv[0]);
+    exit(-1);
+  }
+}
+
+int main(int argc, char **argv) {
+  cf_t *buffer; 
+  int frame_cnt, n; 
+  void *uhd;
+  pss_synch_t pss; 
+  int32_t flen; 
+  int peak_idx, last_peak;
+  float peak_value; 
+  float mean_peak; 
+  uint32_t nof_det, nof_nodet, nof_nopeak, nof_nopeakdet;
+  
+  parse_args(argc, argv);
+
+  flen = 4800*(fft_size/64);
+  
+  buffer = malloc(sizeof(cf_t) * flen);
+  if (!buffer) {
+    perror("malloc");
+    exit(-1);
+  }
+    
+  if (pss_synch_init_fft(&pss, flen, fft_size)) {
+    fprintf(stderr, "Error initiating PSS\n");
+    exit(-1);
+  }
+  if (pss_synch_set_N_id_2(&pss, N_id_2)) {
+    fprintf(stderr, "Error setting N_id_2=%d\n",N_id_2);
+    exit(-1);
+  }
+  
+  printf("Opening UHD device...\n");
+  if (cuhd_open(uhd_args, &uhd)) {
+    fprintf(stderr, "Error opening uhd\n");
+    exit(-1);
+  }
+  printf("Set RX rate: %.2f MHz\n", cuhd_set_rx_srate(uhd, flen*2*100) / 1000000);
+  printf("Set RX gain: %.1f dB\n", cuhd_set_rx_gain(uhd, uhd_gain));
+  printf("Set RX freq: %.2f MHz\n", cuhd_set_rx_freq(uhd, uhd_freq) / 1000000);
+  cuhd_rx_wait_lo_locked(uhd);
+  cuhd_start_rx_stream(uhd);
+  
+  printf("Frame length %d samples\n", flen);
+  printf("PSS detection threshold: %.2f\n", threshold);
+  
+  nof_det = nof_nodet = nof_nopeak = nof_nopeakdet = 0;
+  frame_cnt = 0;
+  last_peak = 0; 
+  mean_peak = 0;
+  while(frame_cnt < nof_frames || nof_frames == -1) {
+    n = cuhd_recv(uhd, buffer, flen, 1);
+    if (n < 0) {
+      fprintf(stderr, "Error receiving samples\n");
+      exit(-1);
+    }
+
+    peak_idx = pss_synch_find_pss(&pss, buffer, &peak_value);
+    if (peak_idx < 0) {
+      fprintf(stderr, "Error finding PSS peak\n");
+      exit(-1);
+    }
+        
+    float y = sqrtf(crealf(vec_dot_prod_conj_ccc(&buffer[peak_idx-fft_size], 
+                                                 &buffer[peak_idx-fft_size], 
+                                                 fft_size)) /
+                                                 fft_size);
+    float x = peak_value/y;
+    
+    mean_peak = EXPAVERAGE(x, mean_peak, frame_cnt);
+    
+    if (x >= threshold) {
+      nof_det++;
+    } else {
+      nof_nodet++;
+    }
+
+    if (frame_cnt > 100) {
+      if (abs(last_peak-peak_idx) > 10) {
+        if (x >= threshold) {
+          nof_nopeakdet++;
+        } else {
+          if (nof_nodet > 0) {
+            nof_nodet--;            
+          }
+        }
+        nof_nopeak++;
+      } 
+    }
+
+    frame_cnt++;
+
+    printf("[%5d]: Pos: %5d, En: %.4f Val: %.3f MeanVal: %.3f, Det: %.3f, No-Det: %.3f, NoPeak: %.3f, NoPeakDet: %.3f\r",
+           frame_cnt, 
+           peak_idx, y, x, mean_peak,
+           (float) nof_det/frame_cnt, (float) nof_nodet/frame_cnt, 
+           (float) nof_nopeak/frame_cnt, (float) nof_nopeakdet/nof_nopeak);
+    
+    if (VERBOSE_ISINFO()) {
+      printf("\n");
+    }
+    
+    last_peak = peak_idx;
+
+  }
+  
+  pss_synch_free(&pss);
+  free(buffer);
+  cuhd_close(uhd);
+
+  printf("Ok\n");
+  exit(0);
+}
+

lte/phy/lib/sync/test/sync_test.c

@@ -32,18 +32,21 @@
 #include <unistd.h>
 #include <math.h>
 #include <time.h>
+
 #include <stdbool.h>
 
 #include "liblte/phy/phy.h"
 
 int cell_id = -1, offset = 0;
 lte_cp_t cp = CPNORM;
+uint32_t nof_prb=6; 
 
-#define FLEN  9600
+#define FLEN  SF_LEN(fft_size)
 
 void usage(char *prog) {
-  printf("Usage: %s [coev]\n", prog);
+  printf("Usage: %s [cpoev]\n", prog);
   printf("\t-c cell_id [Default check for all]\n");
+  printf("\t-p nof_prb [Default %d]\n", nof_prb);
   printf("\t-o offset [Default %d]\n", offset);
   printf("\t-e extended CP [Default normal]\n");
   printf("\t-v verbose\n");
@@ -51,11 +54,14 @@ void usage(char *prog) {
 
 void parse_args(int argc, char **argv) {
   int opt;
-  while ((opt = getopt(argc, argv, "coev")) != -1) {
+  while ((opt = getopt(argc, argv, "cpoev")) != -1) {
     switch (opt) {
     case 'c':
       cell_id = atoi(argv[optind]);
       break;
+    case 'p':
+      nof_prb = atoi(argv[optind]);
+      break;
     case 'o':
       offset = atoi(argv[optind]);
       break;
@@ -82,32 +88,40 @@ int main(int argc, char **argv) {
   uint32_t find_idx;
   sync_t sync;
   lte_fft_t ifft;
+  int fft_size; 
   
   parse_args(argc, argv);
 
+  fft_size = lte_symbol_sz(nof_prb);
+  if (fft_size < 0) {
+    fprintf(stderr, "Invalid nof_prb=%d\n", nof_prb);
+    exit(-1);
+  }
+
   buffer = malloc(sizeof(cf_t) * FLEN);
   if (!buffer) {
     perror("malloc");
     exit(-1);
   }
 
-  fft_buffer = malloc(sizeof(cf_t) * 2 * FLEN);
+  fft_buffer = malloc(sizeof(cf_t) * FLEN);
   if (!fft_buffer) {
     perror("malloc");
     exit(-1);
   }
   
-  if (lte_ifft_init(&ifft, cp, 6)) {
+  if (lte_ifft_init(&ifft, cp, nof_prb)) {
     fprintf(stderr, "Error creating iFFT object\n");
     exit(-1);
   }
 
-  if (sync_init(&sync, FLEN, 128, 128)) {
+  if (sync_init(&sync, FLEN, fft_size)) {
     fprintf(stderr, "Error initiating PSS/SSS\n");
     return -1;
   }
 
-  sync_set_threshold(&sync, 1, 1);
+  /* Set a very high threshold to make sure the correlation is ok */
+  sync_set_threshold(&sync, 1.4);
 
   if (cell_id == -1) {
     cid = 0;
@@ -123,21 +137,28 @@ int main(int argc, char **argv) {
     pss_generate(pss_signal, N_id_2);
     sss_generate(sss_signal0, sss_signal5, cid);
 
+    sync_set_N_id_2(&sync, N_id_2);
+    
     for (ns=0;ns<2;ns++) {
       memset(buffer, 0, sizeof(cf_t) * FLEN);
-      pss_put_slot(pss_signal, buffer, 6, cp);
+      pss_put_slot(pss_signal, buffer, nof_prb, cp);
-      sss_put_slot(ns?sss_signal5:sss_signal0, buffer, 6, cp);
+      sss_put_slot(ns?sss_signal5:sss_signal0, buffer, nof_prb, cp);
 
       /* Transform to OFDM symbols */
-      memset(fft_buffer, 0, sizeof(cf_t) * 2 * FLEN);
+      memset(fft_buffer, 0, sizeof(cf_t) * FLEN);
       lte_ifft_run_slot(&ifft, buffer, &fft_buffer[offset]);
       
-      sync_find(&sync, fft_buffer, &find_idx);
+      vec_save_file("input", fft_buffer, sizeof(cf_t) * FLEN);
-      find_ns = sync_get_slot_id(&sync);
+
+      if (sync_find(&sync, fft_buffer, 0, &find_idx) < 0) {
+        fprintf(stderr, "Error running sync_find\n");
+        exit(-1);
+      }
+      find_ns = 2*sync_get_sf_idx(&sync);
       printf("cell_id: %d find: %d, offset: %d, ns=%d find_ns=%d\n", cid, find_idx, offset,
           ns, find_ns);
-      if (find_idx != offset + 960) {
+      if (find_idx != offset + FLEN/2) {
-        printf("offset != find_offset: %d != %d\n", find_idx, offset + 960);
+        printf("offset != find_offset: %d != %d\n", find_idx, offset + FLEN/2);
         exit(-1);
       }
       if (ns*10 != find_ns) {

lte/phy/lib/ue/src/ue_celldetect.c

@@ -0,0 +1,268 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+
+#include "liblte/phy/ue/ue_celldetect.h"
+
+#include "liblte/phy/utils/debug.h"
+#include "liblte/phy/utils/vector.h"
+
+#define FIND_FFTSIZE   64
+#define FIND_SFLEN     5*SF_LEN(FIND_FFTSIZE)
+
+int ue_celldetect_init(ue_celldetect_t * q) {
+  return ue_celldetect_init_max(q, CS_DEFAULT_MAXFRAMES_TOTAL, CS_DEFAULT_MAXFRAMES_DETECTED); 
+}
+
+int ue_celldetect_init_max(ue_celldetect_t * q, uint32_t max_frames_total, uint32_t max_frames_detected) {
+  int ret = LIBLTE_ERROR_INVALID_INPUTS;
+
+  if (q != NULL) {
+    ret = LIBLTE_ERROR;
+
+    bzero(q, sizeof(ue_celldetect_t));
+
+    q->candidates = malloc(sizeof(ue_celldetect_result_t) * max_frames_detected);
+    if (!q->candidates) {
+      perror("malloc");
+      goto clean_exit; 
+    }
+    if (sync_init(&q->sfind, FIND_SFLEN, FIND_FFTSIZE)) {
+      goto clean_exit;
+    }
+    q->mode_ntimes = malloc(sizeof(uint32_t) * max_frames_detected);
+    if (!q->mode_ntimes) {
+      perror("malloc");
+      goto clean_exit;  
+    }
+    q->mode_counted = malloc(sizeof(char) * max_frames_detected);
+    if (!q->mode_counted) {
+      perror("malloc");
+      goto clean_exit;  
+    }
+
+    sync_set_threshold(&q->sfind, CS_FIND_THRESHOLD);
+    sync_sss_en(&q->sfind, true);
+
+    q->max_frames_total = max_frames_total;
+    q->max_frames_detected = max_frames_detected;
+    q->nof_frames_total = CS_DEFAULT_NOFFRAMES_TOTAL; 
+    q->nof_frames_detected = CS_DEFAULT_NOFFRAMES_DETECTED; 
+
+    ue_celldetect_reset(q);
+    
+    ret = LIBLTE_SUCCESS;
+  }
+
+clean_exit:
+  if (ret == LIBLTE_ERROR) {
+    ue_celldetect_free(q);
+  }
+  return ret;
+}
+
+void ue_celldetect_free(ue_celldetect_t * q)
+{
+  if (q->candidates) {
+    free(q->candidates);
+  }
+  if (q->mode_counted) {
+    free(q->mode_counted);
+  }
+  if (q->mode_ntimes) {
+    free(q->mode_ntimes);
+  }
+  sync_free(&q->sfind);
+}
+
+
+void ue_celldetect_reset(ue_celldetect_t * q)
+{
+  q->current_nof_detected = 0; 
+  q->current_nof_total = 0; 
+  q->current_N_id_2 = 0; 
+}
+
+void ue_celldetect_set_threshold(ue_celldetect_t * q, float threshold)
+{
+  sync_set_threshold(&q->sfind, threshold);
+}
+
+int ue_celldetect_set_nof_frames_total(ue_celldetect_t * q, uint32_t nof_frames)
+{
+  if (nof_frames <= q->max_frames_total) {
+    q->nof_frames_total = nof_frames;    
+    return LIBLTE_SUCCESS; 
+  } else {
+    return LIBLTE_ERROR;
+  }
+}
+
+int ue_celldetect_set_nof_frames_detected(ue_celldetect_t * q, uint32_t nof_frames)
+{
+  if (nof_frames <= q->max_frames_detected) {
+    q->nof_frames_detected = nof_frames;    
+    return LIBLTE_SUCCESS; 
+  } else {
+    return LIBLTE_ERROR;
+  }
+}
+
+/* Decide the most likely cell based on the mode */
+void decide_cell(ue_celldetect_t * q, ue_celldetect_result_t *found_cell)
+{
+  uint32_t i, j;
+  
+  bzero(q->mode_counted, q->nof_frames_detected);
+  bzero(q->mode_ntimes, sizeof(uint32_t) * q->nof_frames_detected);
+  
+  /* First find mode of CELL IDs */
+  for (i = 0; i < q->nof_frames_detected; i++) {
+    uint32_t cnt = 1;
+    for (j=i+1;j<q->nof_frames_detected;j++) {
+      if (q->candidates[j].cell_id == q->candidates[i].cell_id && !q->mode_counted[j]) {
+        q->mode_counted[j]=1;
+        cnt++;
+      }
+    }
+    q->mode_ntimes[i] = cnt; 
+  }
+  uint32_t max_times=0, mode_pos=0; 
+  for (i=0;i<q->nof_frames_detected;i++) {
+    if (q->mode_ntimes[i] > 0) {
+      DEBUG("ntimes[%d]=%d (CID: %d)\n",i,q->mode_ntimes[i],q->candidates[i].cell_id);      
+    }
+    if (q->mode_ntimes[i] > max_times) {
+      max_times = q->mode_ntimes[i];
+      mode_pos = i;
+    }
+  }
+  found_cell->cell_id = q->candidates[mode_pos].cell_id;
+  /* Now in all these cell IDs, find most frequent CP */
+  uint32_t nof_normal = 0;
+  found_cell->peak = 0; 
+  for (i=0;i<q->nof_frames_detected;i++) {
+    if (q->candidates[i].cell_id == found_cell->cell_id) {
+      if (CP_ISNORM(q->candidates[i].cp)) {
+        nof_normal++;
+      } 
+      found_cell->peak += q->candidates[i].peak/q->mode_ntimes[mode_pos];
+    }
+  }
+  if (nof_normal > q->mode_ntimes[mode_pos]/2) {
+    found_cell->cp = CPNORM;
+  } else {
+    found_cell->cp = CPEXT; 
+  }
+  found_cell->mode = q->mode_ntimes[mode_pos];  
+}
+
+int ue_celldetect_scan(ue_celldetect_t * q, 
+                       cf_t *signal, 
+                       uint32_t nsamples,
+                       ue_celldetect_result_t *found_cell)
+{
+  int ret = LIBLTE_ERROR_INVALID_INPUTS;
+  uint32_t peak_idx;
+  uint32_t nof_input_frames; 
+
+
+  if (q                 != NULL &&
+      signal            != NULL && 
+      nsamples          >= 4800) 
+  {
+    ret = LIBLTE_SUCCESS; 
+    
+    if (nsamples % 4800) {
+      printf("Warning: nsamples must be a multiple of 4800. Some samples will be ignored\n");
+      nsamples = (nsamples/4800) * 4800;
+    }
+    nof_input_frames = nsamples/4800; 
+    
+    for (uint32_t nf=0;nf<nof_input_frames;nf++) {
+      sync_set_N_id_2(&q->sfind, q->current_N_id_2);
+
+      DEBUG("[%3d/%3d]: Searching cells with N_id_2=%d. %d frames\n", 
+           q->current_nof_detected, q->current_nof_total, q->current_N_id_2, nof_input_frames);
+
+      /* Find peak and cell id */
+      ret = sync_find(&q->sfind, &signal[nf*4800], 0, &peak_idx);
+      if (ret < 0) {
+        fprintf(stderr, "Error finding correlation peak (%d)\n", ret);
+        return -1;
+      }
+
+      /* If peak position does not allow to read SSS, return error -3 */
+      if (ret == LIBLTE_SUCCESS && peak_idx != 0) {
+        return CS_FRAME_UNALIGNED; 
+      }
+
+      /* Process the peak result */
+      if (ret == 1) {
+        if (sync_sss_detected(&q->sfind)) {
+          ret = sync_get_cell_id(&q->sfind);
+          if (ret >= 0) {
+            /* Save cell id, cp and peak */
+            q->candidates[q->current_nof_detected].cell_id = (uint32_t) ret;
+            q->candidates[q->current_nof_detected].cp = sync_get_cp(&q->sfind);
+            q->candidates[q->current_nof_detected].peak = sync_get_last_peak_value(&q->sfind);
+          }
+          INFO
+            ("[%3d/%3d]: Found peak at %4d, value %.3f, Cell_id: %d CP: %s\n",
+              q->current_nof_detected, q->current_nof_total, peak_idx,
+              q->candidates[q->current_nof_detected].peak, q->candidates[q->current_nof_detected].cell_id,
+              lte_cp_string(q->candidates[q->current_nof_detected].cp));
+          q->current_nof_detected++;
+        }
+      }
+      q->current_nof_total++; 
+      
+      /* Decide cell ID and CP if we detected up to nof_frames_detected */
+      if (q->current_nof_detected == q->nof_frames_detected) {
+        decide_cell(q, found_cell);
+        q->current_N_id_2++;
+        q->current_nof_detected = q->current_nof_total = 0; 
+        ret = CS_CELL_DETECTED;
+      /* Or go to the next N_id_2 if we didn't detect the cell */
+      } else if (q->current_nof_total == q->nof_frames_total) {
+        q->current_N_id_2++; 
+        q->current_nof_detected = q->current_nof_total = 0; 
+        ret = CS_CELL_NOT_DETECTED; 
+      }    
+      if (q->current_N_id_2 == 3) {
+        q->current_N_id_2 = 0; 
+      }
+    } 
+  }
+
+  return ret;
+}

lte/phy/lib/ue/src/ue_dl.c

@@ -25,8 +25,10 @@
  *
  */
 
-#include "liblte/phy/phch/ue_dl.h"
+#include "liblte/phy/ue/ue_dl.h"
 
+#include <complex.h>
+#include <math.h>
 
 #define EXPAVERAGE(data, average, nframes) ((data + average * nframes) / (nframes + 1))  
 
@@ -54,6 +56,8 @@ int ue_dl_init(ue_dl_t *q,
     q->pkt_errors = 0;
     q->pkts_total = 0; 
     q->nof_trials = 0;
+    q->sfn = 0; 
+    q->pbch_decoded = false; 
     
     if (lte_fft_init(&q->fft, q->cell.cp, q->cell.nof_prb)) {
       fprintf(stderr, "Error initiating FFT\n");
@@ -67,7 +71,10 @@ int ue_dl_init(ue_dl_t *q,
       fprintf(stderr, "Error initiating REGs\n");
       goto clean_exit;
     }
-
+    if (pbch_init(&q->pbch, q->cell)) {
+      fprintf(stderr, "Error creating PBCH object\n");
+      goto clean_exit; 
+    }
     if (pcfich_init(&q->pcfich, &q->regs, q->cell)) {
       fprintf(stderr, "Error creating PCFICH object\n");
       goto clean_exit;
@@ -119,6 +126,7 @@ void ue_dl_free(ue_dl_t *q) {
     lte_fft_free(&q->fft);
     chest_free(&q->chest);
     regs_free(&q->regs);
+    pbch_free(&q->pbch);
     pcfich_free(&q->pcfich);
     pdcch_free(&q->pdcch);
     pdsch_free(&q->pdsch);
@@ -136,7 +144,10 @@ void ue_dl_free(ue_dl_t *q) {
   }
 }
 
-int ue_dl_receive(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint32_t sfn, uint16_t rnti) 
+LIBLTE_API float mean_exec_time=0; 
+int frame_cnt=0;
+
+int ue_dl_decode(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint16_t rnti) 
 {
   uint32_t cfi, cfi_distance, i;
   ra_pdsch_t ra_dl;
@@ -145,19 +156,49 @@ int ue_dl_receive(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint32_t
   uint32_t nof_locations;
   uint16_t crc_rem; 
   dci_format_t format; 
+  pbch_mib_t mib; 
   int ret = LIBLTE_ERROR; 
-  
+  cf_t *ce_slot1[MAX_PORTS];
-  /* If we are looking for SI Blocks, search only in appropiate places */
+  struct timeval t[3]; 
-  if ((rnti == SIRNTI && (sfn % 2) == 0 && sf_idx == 5) ||
-       rnti != SIRNTI)
-  {
 
   /* Run FFT for all subframe data */
   lte_fft_run_sf(&q->fft, input, q->sf_symbols);
 
+  gettimeofday(&t[1], NULL);
+
   /* Get channel estimates for each port */
   chest_ce_sf(&q->chest, q->sf_symbols, q->ce, sf_idx);
  
+  gettimeofday(&t[2], NULL);
+  get_time_interval(t);
+  mean_exec_time = (float) EXPAVERAGE((float) t[0].tv_usec, mean_exec_time, frame_cnt);
+  frame_cnt++;
+  
+  for (int i=0;i<MAX_PORTS;i++) {
+    ce_slot1[i] = &q->ce[i][SLOT_LEN_RE(q->cell.nof_prb, q->cell.cp)];
+  }
+
+  /* Decode PBCH if not yet decoded to obtain the System Frame Number (SFN) */
+  if (sf_idx == 0) {
+    // FIXME: There is no need to do this every frame!
+    pbch_decode_reset(&q->pbch);
+    if (pbch_decode(&q->pbch, &q->sf_symbols[SLOT_LEN_RE(q->cell.nof_prb, q->cell.cp)], ce_slot1, &mib) == 1) {
+      q->sfn = mib.sfn;
+      q->pbch_decoded = true;
+      INFO("Decoded SFN: %d\n", q->sfn);
+    } else {
+      INFO("Not decoded MIB (SFN: %d)\n", q->sfn);
+      q->sfn++; 
+      if (q->sfn == 1024) {
+        q->sfn = 0; 
+      }
+    }
+  }
+  /* If we are looking for SI Blocks, search only in appropiate places */
+  if (((rnti == SIRNTI && (q->sfn % 2) == 0 && sf_idx == 5) ||
+       rnti != SIRNTI))
+  {
+    
     /* First decode PCFICH and obtain CFI */
     if (pcfich_decode(&q->pcfich, q->sf_symbols, q->ce, sf_idx, &cfi, &cfi_distance)<0) {
       fprintf(stderr, "Error decoding PCFICH\n");
@@ -180,6 +221,7 @@ int ue_dl_receive(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint32_t
       format = Format1;
     }
 
+
     crc_rem = 0;
     for (i=0;i<nof_locations && crc_rem != rnti;i++) {
       if (pdcch_extract_llr(&q->pdcch, q->sf_symbols, q->ce, locations[i], sf_idx, cfi)) {
@@ -193,7 +235,6 @@ int ue_dl_receive(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint32_t
       INFO("Decoded DCI message RNTI: 0x%x\n", crc_rem);
     }
       
-    
     if (crc_rem == rnti) {
       if (dci_msg_to_ra_dl(&dci_msg, rnti, q->user_rnti, q->cell, cfi, &ra_dl)) {
         fprintf(stderr, "Error unpacking PDSCH scheduling DCI message\n");
@@ -202,7 +243,7 @@ int ue_dl_receive(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint32_t
 
       uint32_t rvidx; 
       if (rnti == SIRNTI) {
-        switch((sfn%8)/2) {
+        switch((q->sfn%8)/2) {
           case 0: 
             rvidx = 0; 
             break;
@@ -251,7 +292,7 @@ int ue_dl_receive(ue_dl_t *q, cf_t *input, char *data, uint32_t sf_idx, uint32_t
         }
       }
     }
-    if (rnti == SIRNTI && (sfn%8) == 0) {
+    if (rnti == SIRNTI && (q->sfn%8) == 0) {
       q->nof_trials++;      
     }
   }

lte/phy/lib/ue/src/ue_mib.c

@@ -0,0 +1,225 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+
+#include "liblte/phy/ue/ue_mib.h"
+
+#include "liblte/phy/utils/debug.h"
+#include "liblte/phy/utils/vector.h"
+
+#define FIND_FFTSIZE   128
+#define FIND_SFLEN     10*SF_LEN(FIND_FFTSIZE)
+
+int ue_mib_init(ue_mib_t * q, 
+                       uint32_t cell_id, 
+                       lte_cp_t cp) 
+{
+  int ret = LIBLTE_ERROR_INVALID_INPUTS;
+
+  if (q != NULL) {
+
+    ret = LIBLTE_ERROR;
+
+    lte_cell_t cell; 
+    cell.nof_ports = MIB_NOF_PORTS;
+    cell.nof_prb = 6; 
+    cell.id = cell_id; 
+    cell.cp = cp; 
+    
+    q->cell_id = cell_id; 
+    
+    bzero(q, sizeof(ue_mib_t));
+    
+    q->slot1_symbols = malloc(SLOT_LEN_RE(6, cp) * sizeof(cf_t));
+    if (!q->slot1_symbols) {
+      perror("malloc");
+      goto clean_exit;
+    }
+    
+    for (int i=0;i<MIB_NOF_PORTS;i++) {
+      q->ce[i] = malloc(SLOT_LEN_RE(6, cp) * sizeof(cf_t));
+      if (!q->ce[i]) {
+        perror("malloc");
+        goto clean_exit;
+      }
+    }
+
+    if (sync_init(&q->sfind, FIND_SFLEN, FIND_FFTSIZE)) {
+      goto clean_exit;
+    }
+    
+    sync_set_threshold(&q->sfind, MIB_FIND_THRESHOLD);
+    sync_sss_en(&q->sfind, true);
+    sync_set_N_id_2(&q->sfind, cell_id % 3);
+
+    if (lte_fft_init(&q->fft, cp, cell.nof_prb)) {
+      fprintf(stderr, "Error initializing FFT\n");
+      goto clean_exit;
+    }
+    if (chest_init_LTEDL(&q->chest, cell)) {
+      fprintf(stderr, "Error initializing reference signal\n");
+      goto clean_exit;
+    }
+    if (pbch_init(&q->pbch, cell)) {
+      fprintf(stderr, "Error initiating PBCH\n");
+      goto clean_exit;
+    }
+    ue_mib_reset(q);
+    
+    ret = LIBLTE_SUCCESS;
+  }
+
+clean_exit:
+  if (ret == LIBLTE_ERROR) {
+    ue_mib_free(q);
+  }
+  return ret;
+}
+
+void ue_mib_free(ue_mib_t * q)
+{
+  if (q->slot1_symbols) {
+    free(q->slot1_symbols);
+  }
+  for (int i=0;i<MIB_NOF_PORTS;i++) {
+    if (q->ce[i]) {
+      free(q->ce[i]);
+    }
+  }
+  sync_free(&q->sfind);
+  chest_free(&q->chest);
+  pbch_free(&q->pbch);
+  lte_fft_free(&q->fft);
+}
+
+
+void ue_mib_reset(ue_mib_t * q)
+{
+  q->frame_cnt = 0; 
+  q->last_frame_trial = 0;
+  
+  pbch_decode_reset(&q->pbch);
+}
+
+void ue_mib_set_threshold(ue_mib_t * q, float threshold)
+{
+  sync_set_threshold(&q->sfind, threshold);
+}
+
+static int mib_decoder_run(ue_mib_t * q, cf_t *input, pbch_mib_t *mib)
+{
+  int ret;
+
+  /* Run FFT for the slot symbols */
+  lte_fft_run_slot(&q->fft, input, q->slot1_symbols);
+
+  /* Get channel estimates of slot #1 for each port */
+  ret = chest_ce_slot(&q->chest, q->slot1_symbols, q->ce, 1);
+  if (ret == LIBLTE_SUCCESS) {
+    
+    /* Reset decoder if we missed a frame */
+    if ((q->last_frame_trial && (q->frame_cnt - q->last_frame_trial > 2)) || 
+        q->frame_cnt > 10) 
+    {
+      ue_mib_reset(q);
+      INFO("Resetting PBCH decoder: last trial %u, now is %u\n",
+          q->last_frame_trial, q->frame_cnt);
+    }
+    
+    /* Decode PBCH */
+    ret = pbch_decode(&q->pbch, q->slot1_symbols, q->ce, mib);
+    if (ret < 0) {
+      fprintf(stderr, "Error decoding PBCH\n");      
+    } else if (ret == 1) {
+      INFO("MIB decoded: %u\n", q->frame_cnt/2);
+      ue_mib_reset(q);
+      ret = 1; 
+    } else {
+      INFO("MIB not decoded: %u\n", q->frame_cnt / 2);
+      q->last_frame_trial = q->frame_cnt;
+    }    
+  }
+  return ret;
+}
+
+int ue_mib_decode(ue_mib_t * q, 
+                  cf_t *signal, 
+                  uint32_t nsamples,
+                  pbch_mib_t *mib)
+{
+  int ret = LIBLTE_ERROR_INVALID_INPUTS;
+  uint32_t peak_idx;
+  uint32_t nof_input_frames; 
+
+
+  if (q                 != NULL &&
+      signal            != NULL) 
+  {
+    ret = LIBLTE_SUCCESS; 
+    
+    if (nsamples % MIB_FRAME_SIZE) {
+      printf("Warning: nsamples must be a multiple of %d. Some samples will be ignored\n", MIB_FRAME_SIZE);
+      nsamples = (nsamples/MIB_FRAME_SIZE) * MIB_FRAME_SIZE;
+    }
+    nof_input_frames = nsamples/MIB_FRAME_SIZE; 
+    
+    for (uint32_t nf=0;nf<nof_input_frames;nf++) {
+
+      /* Find peak and cell id */
+      ret = sync_find(&q->sfind, signal, nf*MIB_FRAME_SIZE, &peak_idx);
+      if (ret < 0) {
+        fprintf(stderr, "Error finding correlation peak (%d)\n", ret);
+        return -1;
+      }
+
+      /* If peak position does not allow to read SSS, return error -3 */
+      if (ret                                    == 1        && 
+          nf*MIB_FRAME_SIZE + peak_idx + 960     <= nsamples &&
+          sync_sss_detected(&q->sfind)                       && 
+          sync_get_sf_idx(&q->sfind)             == 0) 
+      {
+        
+        ret = mib_decoder_run(q, &signal[nf*MIB_FRAME_SIZE+peak_idx], mib);
+        
+      } else if ((ret == LIBLTE_SUCCESS && peak_idx != 0)   || 
+                 (ret == 1              && nf*MIB_FRAME_SIZE + peak_idx + 960 > nsamples)) 
+      {
+        ret = MIB_FRAME_UNALIGNED; 
+      } else {
+        ret = 0; 
+      }
+      
+      q->frame_cnt++;
+    } 
+  }
+  return ret;
+}

lte/phy/lib/ue/src/ue_sync.c

@@ -0,0 +1,353 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+#include <unistd.h>
+
+
+#include "liblte/phy/ue/ue_sync.h"
+
+#include "liblte/phy/utils/debug.h"
+#include "liblte/phy/utils/vector.h"
+
+#define MAX_TIME_OFFSET 128
+cf_t dummy[MAX_TIME_OFFSET];
+
+#define CURRENT_FFTSIZE   lte_symbol_sz(q->cell.nof_prb)
+#define CURRENT_SFLEN     SF_LEN(CURRENT_FFTSIZE)
+
+#define CURRENT_SLOTLEN_RE SLOT_LEN_RE(q->cell.nof_prb, q->cell.cp)
+#define CURRENT_SFLEN_RE SF_LEN_RE(q->cell.nof_prb, q->cell.cp)
+
+#define FIND_THRESHOLD          1.0
+#define TRACK_THRESHOLD         0.2
+
+
+int ue_sync_init(ue_sync_t *q, 
+                 lte_cell_t cell,
+                 int (recv_callback)(void*, void*, uint32_t),
+                 void *stream_handler) 
+{
+  int ret = LIBLTE_ERROR_INVALID_INPUTS;
+  
+  if (q                    != NULL && 
+      stream_handler       != NULL && 
+      lte_cell_isvalid(&cell)      &&
+      recv_callback        != NULL)
+  {
+    ret = LIBLTE_ERROR;
+    
+    bzero(q, sizeof(ue_sync_t));
+
+    ue_sync_reset(q);
+    
+    q->decode_sss_on_track = false; 
+    q->stream = stream_handler;
+    q->recv_callback = recv_callback;
+    q->cell = cell;
+    
+    if(sync_init(&q->sfind, CURRENT_SFLEN, CURRENT_FFTSIZE)) {
+      fprintf(stderr, "Error initiating sync find\n");
+      goto clean_exit;
+    }
+    if(sync_init(&q->strack, CURRENT_FFTSIZE, CURRENT_FFTSIZE)) {
+      fprintf(stderr, "Error initiating sync track\n");
+      goto clean_exit;
+    }
+    
+    sync_set_N_id_2(&q->sfind, cell.id%3);
+    sync_set_threshold(&q->sfind, FIND_THRESHOLD);
+    q->sfind.cp = cell.cp;
+    sync_cp_en(&q->sfind, false);
+
+    sync_set_N_id_2(&q->strack, cell.id%3);
+    sync_set_threshold(&q->strack, TRACK_THRESHOLD);
+    q->strack.cp = cell.cp;
+    sync_cp_en(&q->strack, false);
+
+    if (cfo_init(&q->cfocorr, CURRENT_SFLEN)) {
+      fprintf(stderr, "Error initiating CFO\n");
+      goto clean_exit;
+    }
+   
+    q->input_buffer = vec_malloc(5 * CURRENT_SFLEN * sizeof(cf_t));
+    if (!q->input_buffer) {
+      perror("malloc");
+      goto clean_exit;
+    }
+    
+    ret = LIBLTE_SUCCESS;
+  }
+  
+clean_exit:
+  if (ret == LIBLTE_ERROR) {
+    ue_sync_free(q);
+  }
+  return ret; 
+}
+
+void ue_sync_free(ue_sync_t *q) {
+  if (q->input_buffer) {
+    free(q->input_buffer);
+  }
+  cfo_free(&q->cfocorr);
+  sync_free(&q->sfind);
+  sync_free(&q->strack);
+}
+
+uint32_t ue_sync_peak_idx(ue_sync_t *q) {
+  return q->peak_idx;
+}
+
+ue_sync_state_t ue_sync_get_state(ue_sync_t *q) {
+  return q->state;
+}
+uint32_t ue_sync_get_sfidx(ue_sync_t *q) {
+  return q->sf_idx;    
+}
+
+float ue_sync_get_cfo(ue_sync_t *q) {
+  return 15000 * q->cur_cfo;
+}
+
+float ue_sync_get_sfo(ue_sync_t *q) {
+  return 1000*q->mean_time_offset/5;
+}
+
+void ue_sync_decode_sss_on_track(ue_sync_t *q, bool enabled) {
+  q->decode_sss_on_track = enabled; 
+}
+
+
+static int find_peak_ok(ue_sync_t *q) {
+
+  /* Receive the rest of the next subframe */
+  if (q->recv_callback(q->stream, q->input_buffer, q->peak_idx+CURRENT_SFLEN/2) < 0) {
+    return LIBLTE_ERROR;
+  }
+  
+  if (sync_sss_detected(&q->sfind)) {
+    
+    /* Get the subframe index (0 or 5) */
+    q->sf_idx = sync_get_sf_idx(&q->sfind) + 1;
+   
+    /* Reset variables */ 
+    q->frame_ok_cnt = 0;
+    q->frame_no_cnt = 0;
+    q->frame_total_cnt = 0;       
+
+    /* Goto Tracking state */
+    q->state = SF_TRACK;      
+    
+    INFO("Found peak at %d, value %.3f, SF_idx: %d, Cell_id: %d CP: %s\n", 
+        q->peak_idx, sync_get_peak_value(&q->sfind), q->sf_idx, q->cell.id, lte_cp_string(q->cell.cp));       
+    
+  } else {
+    INFO("Found peak at %d, SSS not detected\n", q->peak_idx);
+  }
+  return 0;
+}
+
+int track_peak_ok(ue_sync_t *q, uint32_t track_idx) {
+  
+   /* Make sure subframe idx is what we expect */
+  if ((q->sf_idx != sync_get_sf_idx(&q->strack)) && q->decode_sss_on_track) {
+    INFO("Warning: Expected SF idx %d but got %d!\n", 
+          q->sf_idx, sync_get_sf_idx(&q->strack));
+    q->sf_idx = sync_get_sf_idx(&q->strack);
+    q->state = SF_TRACK; 
+  } else {
+    q->time_offset = ((int) track_idx - (int) CURRENT_FFTSIZE); 
+    
+    /* If the PSS peak is beyond the frame (we sample too slowly), 
+      discard the offseted samples to align next frame */
+    if (q->time_offset > 0 && q->time_offset < MAX_TIME_OFFSET) {
+      if (q->recv_callback(q->stream, dummy, (uint32_t) q->time_offset) < 0) {
+        fprintf(stderr, "Error receiving from USRP\n");
+        return LIBLTE_ERROR; 
+      }
+    } 
+    
+    /* compute cumulative moving average CFO */
+    q->cur_cfo = EXPAVERAGE(sync_get_cfo(&q->strack), q->cur_cfo, q->frame_ok_cnt);
+    
+    /* compute cumulative moving average time offset */
+    q->mean_time_offset = (float) EXPAVERAGE((float) q->time_offset, q->mean_time_offset, q->frame_ok_cnt);
+
+    q->peak_idx = CURRENT_SFLEN/2 + q->time_offset;  
+    q->frame_ok_cnt++;
+    q->frame_no_cnt = 0;    
+  }
+  
+  return 1;
+}
+
+int track_peak_no(ue_sync_t *q) {
+  
+  /* if we missed too many PSS go back to FIND */
+  q->frame_no_cnt++; 
+  if (q->frame_no_cnt >= TRACK_MAX_LOST) {
+    printf("\n%d frames lost. Going back to FIND\n", (int) q->frame_no_cnt);
+    q->state = SF_FIND;
+  } else {
+    INFO("Tracking peak not found. Peak %.3f, %d lost\n", 
+         sync_get_peak_value(&q->strack), (int) q->frame_no_cnt);    
+  }
+
+  return 1;
+}
+
+static int receive_samples(ue_sync_t *q) {
+  
+  /* A negative time offset means there are samples in our buffer for the next subframe, 
+  because we are sampling too fast. 
+  */
+  if (q->time_offset < 0) {
+    q->time_offset = -q->time_offset;
+  }
+
+  /* copy last part of the last subframe (use move since there could be overlapping) */
+  //memcpy(q->input_buffer, &q->input_buffer[CURRENT_SFLEN-q->time_offset], q->time_offset*sizeof(cf_t));
+  
+  /* Get 1 subframe from the USRP getting more samples and keeping the previous samples, if any */  
+  if (q->recv_callback(q->stream, &q->input_buffer[q->time_offset], CURRENT_SFLEN - q->time_offset) < 0) {
+    return LIBLTE_ERROR;
+  }
+  
+  /* reset time offset */
+  q->time_offset = 0;
+
+  return LIBLTE_SUCCESS; 
+}
+
+int ue_sync_get_buffer(ue_sync_t *q, cf_t **sf_symbols) {
+  int ret = LIBLTE_ERROR_INVALID_INPUTS; 
+  uint32_t track_idx; 
+  struct timeval t[3];
+
+  if (q               != NULL   &&
+      sf_symbols      != NULL   &&
+      q->input_buffer != NULL)
+  {
+    
+    if (receive_samples(q)) {
+      fprintf(stderr, "Error receiving samples\n");
+      return -1;
+    }
+    
+    switch (q->state) {
+      case SF_FIND:        
+        ret = sync_find(&q->sfind, q->input_buffer, 0, &q->peak_idx);
+        if (ret < 0) {
+          fprintf(stderr, "Error finding correlation peak (%d)\n", ret);
+          return -1;
+        }
+        
+        if (ret == 1) {
+          ret = find_peak_ok(q);
+        } else if (q->peak_idx != 0) {
+          uint32_t rlen; 
+          if (q->peak_idx < CURRENT_SFLEN/2) {
+            rlen = CURRENT_SFLEN/2-q->peak_idx;
+          } else {
+            rlen = q->peak_idx;
+          }
+          if (q->recv_callback(q->stream, q->input_buffer, rlen) < 0) {
+            return LIBLTE_ERROR;
+          }
+        }
+      break;
+      case SF_TRACK:
+        ret = 1;
+        
+        q->strack.sss_en = q->decode_sss_on_track; 
+        
+        q->sf_idx = (q->sf_idx + 1) % 10;
+
+        /* Every SF idx 0 and 5, find peak around known position q->peak_idx */
+        if (q->sf_idx == 0 || q->sf_idx == 5) {
+
+          #ifdef MEASURE_EXEC_TIME
+          gettimeofday(&t[1], NULL);
+          #endif
+          
+          track_idx = 0; 
+          
+          /* track pss around the middle of the subframe, where the PSS is */
+          ret = sync_find(&q->strack, q->input_buffer, CURRENT_SFLEN/2-CURRENT_FFTSIZE, &track_idx);
+          if (ret < 0) {
+            fprintf(stderr, "Error tracking correlation peak\n");
+            return -1;
+          }
+          
+          #ifdef MEASURE_EXEC_TIME
+          gettimeofday(&t[2], NULL);
+          get_time_interval(t);
+          q->mean_exec_time = (float) EXPAVERAGE((float) t[0].tv_usec, q->mean_exec_time, q->frame_total_cnt);
+          #endif
+
+          if (ret == 1) {
+            ret = track_peak_ok(q, track_idx);
+          } else {
+            ret = track_peak_no(q); 
+          }
+          if (ret == LIBLTE_ERROR) {
+            fprintf(stderr, "Error processing tracking peak\n");
+            q->state = SF_FIND; 
+            return LIBLTE_SUCCESS;
+          } 
+                    
+          q->frame_total_cnt++;           
+        }
+        
+        /* Do CFO Correction and deliver the frame */
+        cfo_correct(&q->cfocorr, q->input_buffer, q->input_buffer, -q->cur_cfo / CURRENT_FFTSIZE);         
+        *sf_symbols = q->input_buffer;
+        
+      break;
+    }
+  }  
+  return ret; 
+}
+
+void ue_sync_reset(ue_sync_t *q) {
+  q->state = SF_FIND;
+    
+  q->frame_ok_cnt = 0;
+  q->frame_no_cnt = 0;
+  q->frame_total_cnt = 0; 
+  q->cur_cfo = 0;
+  q->mean_time_offset = 0;
+  q->time_offset = 0;
+  #ifdef MEASURE_EXEC_TIME
+  q->mean_exec_time = 0;
+  #endif  
+}
+

lte/phy/lib/ue/test/CMakeLists.txt

@@ -0,0 +1,41 @@
+#
+# Copyright 2012-2013 The libLTE Developers. See the
+# COPYRIGHT file at the top-level directory of this distribution.
+#
+# This file is part of the libLTE library.
+#
+# libLTE is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation, either version 3 of
+# the License, or (at your option) any later version.
+#
+# libLTE is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# A copy of the GNU Lesser General Public License can be found in
+# the LICENSE file in the top-level directory of this distribution
+# and at http://www.gnu.org/licenses/.
+#
+
+########################################################################
+# UE SYNC TEST (Only compiled if CUHD is available)
+########################################################################
+LIST(FIND OPTIONAL_LIBS cuhd CUHD_FIND)
+LIST(FIND OPTIONAL_LIBS graphics GRAPHICS_FIND)
+
+IF(${CUHD_FIND} GREATER -1)
+  ADD_EXECUTABLE(ue_sync_usrp ue_sync_usrp.c)
+  TARGET_LINK_LIBRARIES(ue_sync_usrp lte_phy cuhd)
+
+  ADD_EXECUTABLE(ue_celldetect_mib_test ue_celldetect_mib_test.c)
+  TARGET_LINK_LIBRARIES(ue_celldetect_mib_test lte_phy cuhd)
+ENDIF(${CUHD_FIND} GREATER -1)
+
+IF(${GRAPHICS_FIND} EQUAL -1)
+  SET_TARGET_PROPERTIES(ue_sync_usrp PROPERTIES COMPILE_DEFINITIONS "DISABLE_GRAPHICS")
+ELSE(${GRAPHICS_FIND} EQUAL -1)
+  target_link_libraries(ue_sync_usrp graphics)
+ENDIF(${GRAPHICS_FIND} EQUAL -1)
+

lte/phy/lib/ue/test/ue_celldetect_mib_test.c

@@ -0,0 +1,265 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2014 The libLTE Developers. See the
+ * COPYRIGHT file at the top-level directory of this distribution.
+ *
+ * \section LICENSE
+ *
+ * This file is part of the libLTE library.
+ *
+ * libLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * libLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * A copy of the GNU Lesser General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <math.h>
+#include <complex.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <assert.h>
+#include <signal.h>
+
+#include "liblte/phy/phy.h"
+
+#include "liblte/cuhd/cuhd.h"
+
+int nof_frames_total = CS_DEFAULT_NOFFRAMES_TOTAL;
+int nof_frames_detected = CS_DEFAULT_NOFFRAMES_DETECTED;
+float threshold = -1; 
+
+float uhd_freq = 0.0, uhd_gain = 20.0;
+char *uhd_args = "";
+
+void usage(char *prog) {
+  printf("Usage: %s [agntdv] -f uhd_freq\n", prog);
+  printf("\t-a UHD args [Default %s]\n", uhd_args);
+  printf("\t-g UHD RX gain [Default %.2f dB]\n", uhd_gain);
+  printf("\t-n nof_frames_total [Default 100]\n");
+  printf("\t-d nof_frames_detected [Default 10]\n");
+  printf("\t-t threshold [Default %.2f]\n",threshold);
+  printf("\t-v [set verbose to debug, default none]\n");
+}
+
+void parse_args(int argc, char **argv) {
+  int opt;
+  while ((opt = getopt(argc, argv, "agndtvf")) != -1) {
+    switch (opt) {
+    case 'n':
+      nof_frames_total = atoi(argv[optind]);
+      break;
+    case 'd':
+      nof_frames_detected = atoi(argv[optind]);
+      break;
+    case 'a':
+      uhd_args = argv[optind];
+      break;
+    case 'g':
+      uhd_gain = atof(argv[optind]);
+      break;
+    case 'f':
+      uhd_freq = atof(argv[optind]);
+      break;
+    case 't':
+      threshold = atof(argv[optind]);
+      break;
+    case 'v':
+      verbose++;
+      break;
+    default:
+      usage(argv[0]);
+      exit(-1);
+    }
+  }
+  if (uhd_freq == 0.0) {
+    usage(argv[0]);
+    exit(-1);
+  }
+}
+
+int decode_pbch(void *uhd, cf_t *buffer, ue_celldetect_result_t *found_cell) 
+{
+  ue_mib_t uemib;
+  pbch_mib_t mib; 
+  int n; 
+  
+  uint32_t nof_frames = 0;
+  uint32_t flen = MIB_FRAME_SIZE;
+  
+  if (ue_mib_init(&uemib, found_cell->cell_id, found_cell->cp)) {
+    fprintf(stderr, "Error initiating PBCH decoder\n");
+    return LIBLTE_ERROR;
+  }
+  
+  INFO("Setting sampling frequency 1.92 MHz for PBCH decoding\n", 0);
+  cuhd_set_rx_srate(uhd, 1920000.0);
+  INFO("Starting receiver...\n", 0);
+  cuhd_start_rx_stream(uhd);
+  
+  do {
+    if (cuhd_recv(uhd, buffer, flen, 1)<0) {
+      fprintf(stderr, "Error receiving from USRP\n");
+      return LIBLTE_ERROR;
+    }      
+    
+    INFO("Calling ue_mib_decode() %d/%d\n", nof_frames, nof_frames_total);
+    
+    n = ue_mib_decode(&uemib, buffer, flen, &mib);
+    if (n == LIBLTE_ERROR || n == LIBLTE_ERROR_INVALID_INPUTS) {
+      fprintf(stderr, "Error calling ue_mib_decode()\n");
+      return LIBLTE_ERROR;
+    }
+    if (n == MIB_FRAME_UNALIGNED) {
+      printf("Realigning frame\n");
+      if (cuhd_recv(uhd, buffer, flen/2, 1)<0) {
+        fprintf(stderr, "Error receiving from USRP\n");
+        return LIBLTE_ERROR;
+      }
+    }
+    nof_frames++;
+  } while (n != MIB_FOUND && nof_frames < nof_frames_total);
+  if (n == MIB_FOUND) {
+    printf("\n\nMIB decoded in %d ms (%d half frames)\n", nof_frames*5, nof_frames);
+    pbch_mib_fprint(stdout, &mib, found_cell->cell_id);
+  } else {
+    printf("\nCould not decode MIB\n");
+  }
+
+  cuhd_stop_rx_stream(uhd); 
+  cuhd_flush_buffer(uhd);
+
+  ue_mib_free(&uemib);
+  
+  return LIBLTE_SUCCESS; 
+}
+
+int find_cell(void *uhd, ue_celldetect_t *s, cf_t *buffer, ue_celldetect_result_t *found_cell) 
+{  
+  int n; 
+
+  INFO("Setting sampling frequency 960 KHz for PSS search\n", 0);
+  cuhd_set_rx_srate(uhd, 960000.0);
+  INFO("Starting receiver...\n", 0);
+  cuhd_start_rx_stream(uhd);
+
+  uint32_t nof_scanned_cells = 0; 
+  uint32_t flen = 4800; 
+    
+  do {
+    
+    if (cuhd_recv(uhd, buffer, flen, 1)<0) {
+      fprintf(stderr, "Error receiving from USRP\n");
+      return LIBLTE_ERROR;
+    }
+    
+    n = ue_celldetect_scan(s, buffer, flen, found_cell);
+    switch(n) {
+      case CS_FRAME_UNALIGNED:
+        printf("Realigning frame\n");
+        if (cuhd_recv(uhd, buffer, flen/2, 1)<0) {
+          fprintf(stderr, "Error receiving from USRP\n");
+          return LIBLTE_ERROR;
+        }
+        return LIBLTE_ERROR; 
+      case CS_CELL_DETECTED:
+        if (found_cell->peak > 0) {
+          printf("\tCELL ID: %d, CP: %s, Peak: %.2f, Mode: %d/%d\n", 
+                found_cell->cell_id, lte_cp_string(found_cell->cp), 
+                found_cell->peak, found_cell->mode, s->nof_frames_detected);                      
+        }        
+        nof_scanned_cells++;
+        break;
+      case CS_CELL_NOT_DETECTED:
+        nof_scanned_cells++;
+        break;
+      case LIBLTE_ERROR:
+      case LIBLTE_ERROR_INVALID_INPUTS: 
+        fprintf(stderr, "Error calling cellsearch_scan()\n");
+        return LIBLTE_ERROR;         
+    }
+  } while(nof_scanned_cells < 3 && n != CS_CELL_DETECTED);
+
+  INFO("Stopping receiver...\n", 0);
+  cuhd_stop_rx_stream(uhd); 
+  cuhd_flush_buffer(uhd);
+  
+  return n; 
+}
+
+int main(int argc, char **argv) {
+  int n; 
+  void *uhd;
+  ue_celldetect_t s;
+  ue_celldetect_result_t found_cell; 
+  cf_t *buffer; 
+
+  parse_args(argc, argv);
+    
+  printf("Opening UHD device...\n");
+  if (cuhd_open(uhd_args, &uhd)) {
+    fprintf(stderr, "Error opening uhd\n");
+    exit(-1);
+  }  
+  cuhd_set_rx_gain(uhd, uhd_gain);
+  
+  /* set uhd_freq */
+  cuhd_set_rx_freq(uhd, (double) uhd_freq);
+  cuhd_rx_wait_lo_locked(uhd);
+  DEBUG("Set uhd_freq to %.3f MHz\n", (double ) uhd_freq/1000000);
+  
+  buffer = vec_malloc(sizeof(cf_t) * 96000);
+  if (!buffer) {
+    perror("malloc");
+    return LIBLTE_ERROR;
+  }
+  
+  if (ue_celldetect_init(&s)) {
+    fprintf(stderr, "Error initiating UE sync module\n");
+    exit(-1);
+  }
+  if (threshold > 0) {
+    ue_celldetect_set_threshold(&s, threshold);    
+  }
+  
+  if (nof_frames_total > 0) {
+    ue_celldetect_set_nof_frames_total(&s, nof_frames_total);
+  }
+  if (nof_frames_detected > 0) {
+    ue_celldetect_set_nof_frames_detected(&s, nof_frames_detected);
+  }
+
+  n = find_cell(uhd, &s, buffer, &found_cell);
+  if (n < 0) {
+    fprintf(stderr, "Error searching cell\n");
+    exit(-1);
+  }
+  if (n == CS_CELL_DETECTED) {
+    if (decode_pbch(uhd, buffer, &found_cell)) {
+      fprintf(stderr, "Error decoding PBCH\n");
+      exit(-1);
+    }
+  }
+    
+  ue_celldetect_free(&s);
+  cuhd_close(uhd);
+  exit(0);
+}
+
+

lte/phy/lib/ue/test/ue_sync_usrp.c

@@ -49,16 +49,19 @@ plot_real_t poutfft;
 
 int nof_frames = -1;
 float threshold = -1.0; 
+int N_id_2 = -1;
+uint32_t nof_prb = 6; 
 
 float uhd_freq = 0.0, uhd_gain = 20.0;
 char *uhd_args = "";
 int disable_plots = 0;
 
 void usage(char *prog) {
-  printf("Usage: %s [agntdv] -f uhd_freq\n", prog);
+  printf("Usage: %s [agntdpv] -f uhd_freq -i N_id_2\n", prog);
   printf("\t-a UHD args [Default %s]\n", uhd_args);
   printf("\t-g UHD RX gain [Default %.2f dB]\n", uhd_gain);
   printf("\t-n nof_frames [Default infinite]\n");
+  printf("\t-p nof_prb [Default %d]\n", nof_prb);
   printf("\t-t threshold [Default %.2f]\n",threshold);
   
 #ifndef DISABLE_GRAPHICS
@@ -69,8 +72,14 @@ void usage(char *prog) {
 
 void parse_args(int argc, char **argv) {
   int opt;
-  while ((opt = getopt(argc, argv, "agntdvf")) != -1) {
+  while ((opt = getopt(argc, argv, "agntdvfip")) != -1) {
     switch (opt) {
+    case 'i':
+      N_id_2 = atoi(argv[optind]);
+      break;
+    case 'p':
+      nof_prb = atoi(argv[optind]);
+      break;
     case 'n':
       nof_frames = atoi(argv[optind]);
       break;
@@ -97,7 +106,7 @@ void parse_args(int argc, char **argv) {
       exit(-1);
     }
   }
-  if (uhd_freq == 0.0) {
+  if (uhd_freq == 0.0 || N_id_2 == -1) {
     usage(argv[0]);
     exit(-1);
   }
@@ -117,6 +126,12 @@ void input_init() {
   cuhd_rx_wait_lo_locked(uhd);
   DEBUG("Set uhd_freq to %.3f MHz\n", (double ) uhd_freq/1000000);
 
+  int srate = lte_sampling_freq_hz(nof_prb);
+  if (srate > 0) {
+    cuhd_set_rx_srate(uhd, (double) srate);    
+  } else {
+    fprintf(stderr, "Error invalid nof_prb=%d\n",nof_prb);
+  }
   DEBUG("Starting receiver...\n", 0);
   cuhd_start_rx_stream(uhd);
 
@@ -152,7 +167,6 @@ int main(int argc, char **argv) {
   float peak;
   struct timeval t[3];
   float mean_ce_time=0;
-  bool signal_detected; 
   lte_fft_t fft; 
   lte_cell_t cell; 
   
@@ -168,14 +182,27 @@ int main(int argc, char **argv) {
   
   input_init();
   
-  if (ue_sync_init(&s, cuhd_set_rx_srate, cuhd_recv_wrapper, uhd)) {
+  cell.cp = CPNORM;
+  cell.id = N_id_2;
+  cell.nof_ports = 1;
+  cell.nof_prb = nof_prb;
+        
+  if (ue_sync_init(&s, cell, cuhd_recv_wrapper, uhd)) {
     fprintf(stderr, "Error initiating UE sync module\n");
     exit(-1);
   }
 
-  ue_sync_pbch_enable(&s, true);
+  pss_synch_init_fft(&pss, 
+                    SF_LEN(lte_symbol_sz(cell.nof_prb)), 
+                    lte_symbol_sz(cell.nof_prb));
+  pss_synch_set_N_id_2(&pss, cell.id%3);
+  sf_symbols = vec_malloc(SLOT_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
+  if (!sf_symbols) {
+    perror("malloc");
+    exit(-1);
+  }
+  lte_fft_init(&fft, cell.cp, cell.nof_prb);
 
-  signal_detected = true;
   frame_cnt = 0;
   mean_ce_time=0;
   uint32_t valid_frames=0;
@@ -190,22 +217,6 @@ int main(int argc, char **argv) {
     
     if (n == 1 && ue_sync_get_sfidx(&s) == 0) {
 
-      if (signal_detected) {
-        cell = ue_sync_get_cell(&s);
-        pss_synch_init_fft(&pss, 
-                          SF_LEN(lte_symbol_sz(cell.nof_prb), cell.cp), 
-                          lte_symbol_sz(cell.nof_prb));
-        pss_synch_set_N_id_2(&pss, cell.id%3);
-        
-        sf_symbols = vec_malloc(SLOT_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
-        if (!sf_symbols) {
-          perror("malloc");
-          exit(-1);
-        }
-        lte_fft_init(&fft, cell.cp, cell.nof_prb);
-        signal_detected = false; 
-      }
-      
       mean_ce_time = (float) (mean_ce_time + (float) t[0].tv_usec * valid_frames) / (valid_frames+1);
       valid_frames++;
       
@@ -227,13 +238,9 @@ int main(int argc, char **argv) {
       }
     #endif
       
-      pos = pss_synch_find_pss(&pss, input_buffer, &peak, NULL);      
+      pos = pss_synch_find_pss(&pss, input_buffer, &peak);      
-      /*if (pos > 962 || pos < 958) {
-        unaligned++;
-      }
-      */
       printf("CELL_ID: %3d CFO: %+.4f KHz, SFO: %+.4f Khz, TimeOffset: %4d, Exec: %3.2f\r",
-              cell.id, ue_sync_get_cfo(&s)/1000, ue_sync_get_sfo(&s)/1000, pos, 
+              sync_get_cell_id(&s.sfind), ue_sync_get_cfo(&s)/1000, ue_sync_get_sfo(&s)/1000, pos, 
              s.mean_exec_time);
           fflush(stdout);
       if (VERBOSE_ISINFO()) {

lte/phy/lib/utils/src/convolution.c

@@ -53,6 +53,9 @@ int conv_fft_cc_init(conv_fft_cc_t *q, uint32_t input_len, uint32_t filter_len)
   if (dft_plan(&q->output_plan,q->output_len,BACKWARD,COMPLEX)) {
     return LIBLTE_ERROR;
   }
+  dft_plan_set_norm(&q->input_plan, true);
+  dft_plan_set_norm(&q->filter_plan, true);
+  dft_plan_set_norm(&q->output_plan, false);
   return LIBLTE_SUCCESS;
 }
 
@@ -80,7 +83,7 @@ uint32_t conv_fft_cc_run(conv_fft_cc_t *q, cf_t *input, cf_t *filter, cf_t *outp
 
   dft_run_c(&q->output_plan, q->output_fft, output);
 
-  return q->output_len;
+  return q->output_len-1;
 
 }
 

lte/phy/lib/utils/src/dft.c

@@ -32,6 +32,7 @@
 #include <string.h>
 
 #include "liblte/phy/utils/dft.h"
+#include "liblte/phy/utils/vector.h"
 
 #define dft_ceil(a,b) ((a-1)/b+1)
 #define dft_floor(a,b) (a/b)
@@ -144,11 +145,8 @@ void dft_run_c(dft_plan_t *plan, dft_c_t *in, dft_c_t *out) {
            plan->forward, plan->mirror, plan->dc);
   fftwf_execute(plan->p);
   if (plan->norm) {
-    /**FIXME: Use VOLK */
+    norm = 1.0/sqrtf(plan->size);
-    norm = sqrtf(plan->size);
+    vec_sc_prod_cfc(f_out, norm, f_out, plan->size);    
-    for (i=0;i<plan->size;i++) {
-      f_out[i] /= norm;
-    }
   }
   if (plan->db) {
     for (i=0;i<plan->size;i++) {
@@ -168,10 +166,8 @@ void dft_run_r(dft_plan_t *plan, dft_r_t *in, dft_r_t *out) {
   memcpy(plan->in,in,sizeof(dft_r_t)*plan->size);
   fftwf_execute(plan->p);
   if (plan->norm) {
-    norm = plan->size;
+    norm = 1.0/plan->size;
-    for (i=0;i<len;i++) {
+    vec_sc_prod_fff(f_out, norm, f_out, plan->size);    
-      f_out[i] /= norm;
-    }
   }
   if (plan->db) {
     for (i=0;i<len;i++) {

lte/phy/lib/utils/src/vector.c

@@ -155,6 +155,17 @@ void vec_deinterleave_cf(cf_t *x, float *real, float *imag, uint32_t len) {
 #endif 
 }
 
+void vec_deinterleave_real_cf(cf_t *x, float *real, uint32_t len) {
+#ifdef HAVE_VOLK_DEINTERLEAVE_REAL_FUNCTION
+  volk_32fc_deinterleave_real_32f(real, x, len);
+#else 
+  int i;
+  for (i=0;i<len;i++) {
+    real[i] = __real__ x[i];
+  }
+#endif  
+}
+
 void *vec_malloc(uint32_t size) {
 #ifndef HAVE_VOLK
   return malloc(size);
@@ -413,6 +424,29 @@ uint32_t vec_max_fi(float *x, uint32_t len) {
 #endif
 }
 
+
+uint32_t vec_max_abs_ci(cf_t *x, uint32_t len) {
+#ifdef HAVE_VOLK_MAX_ABS_FUNCTION
+  uint32_t target=0;
+  volk_32fc_index_max_16u(&target,x,len);
+  return target;
+
+#else
+  uint32_t i;
+  float m=-FLT_MAX;
+  uint32_t p=0;
+  float tmp;
+  for (i=0;i<len;i++) {
+    tmp = crealf(x[i])*crealf(x[i]) + cimagf(x[i])*cimagf(x[i]);
+    if (tmp>m) {
+      m=tmp;
+      p=i;
+    }
+  }
+  return p;
+#endif
+}
+
 void vec_quant_fuc(float *in, unsigned char *out, float gain, float offset, float clip, uint32_t len) {
   int i;
   int tmp;

matlab/sync/addnoise.m

@@ -0,0 +1,6 @@
+function [ y ] = addnoise( x, snr_db )
+v = 10^(-snr_db/10);
+y=x+sqrt(v)*(randn(size(x))+1i*randn(size(x)))/sqrt(2);
+y=y/sqrt(mean(y.*conj(y)));
+end
+

matlab/sync/find_peaks.m

@@ -0,0 +1,13 @@
+function [peaks] = find_peaks(x, N_id_2, fft_size)
+
+flen=4800*(ceil(fft_size/64));
+
+n=floor(length(x)/flen)*flen;
+xf=reshape(x(1:n),flen,[]);
+
+[n m] = size(xf);
+
+peaks=zeros(m,1);
+for i=1:m
+    [w, peaks(i)]= find_pss2(xf(:,i),N_id_2,fft_size);
+end

matlab/sync/find_pss2.m

@@ -1,18 +1,14 @@
-function [ fs eps p_m w2] = find_pss( x, N_id_2, fft_size)
+function [w2, m, idx] = find_pss2( x, N_id_2, fft_size)
     c=lte_pss_zc(N_id_2);
     cc=[zeros(fft_size/2-31,1); c; zeros(fft_size/2-31,1)];
-    cc=[0; cc(fft_size/2+1:fft_size); cc(2:fft_size/2)];
+    ccd=[0; cc(fft_size/2+1:fft_size); cc(2:fft_size/2)];
-    ccf=conj(ifft(cc));
+    ccf=sqrt(fft_size)*conj(ifft(ccd));
     
-    w2=conv(x,ccf);
+    w2=abs(conv(x,ccf/62)).^2/var(x,1)/sqrt(2);
-        %plot(10*log10(abs(w2)));%./mean(abs(w2))));
+    plot(w2) 
-   plot(abs(w2)) 
+    [m, idx]=max(w2);
-       %axis([0 length(w2) 0 20])
-    [m i]=max(abs(w2));
-    p_m = m/mean(abs(w2));
-    
-    fprintf('Frame starts at %d, m=%g, p=%g, p/m=%g dB\n',i, ...
-            mean(abs(w2)), m, 10*log10(m/mean(abs(w2))));
     
+    %fprintf('Frame starts at %d, energy=%g, p=%g, p/en=%g dB\n',i, ...
+    %        en, m, m/en);
 end