Fixed pdsch_enodeb, bcch decoding for 20 MHz and CFO correction

lte/examples/pdsch_enodeb.c

@@ -249,6 +249,7 @@ int main(int argc, char **argv) {
   dci_msg_t dci_msg;
   dci_location_t locations[NSUBFRAMES_X_FRAME][10];
   uint32_t sfn; 
+  chest_dl_t est; 
   
 #ifdef DISABLE_UHD
   if (argc < 3) {
@@ -263,6 +264,10 @@ int main(int argc, char **argv) {
   sf_n_re = 2 * CPNORM_NSYMB * cell.nof_prb * RE_X_RB;
   sf_n_samples = 2 * SLOT_LEN(lte_symbol_sz(cell.nof_prb));
 
+  cell.phich_length = PHICH_NORM;
+  cell.phich_resources = R_1;
+  sfn = 0;
+
   /* this *must* be called after setting slot_len_* */
   base_init();
 
@@ -270,12 +275,14 @@ int main(int argc, char **argv) {
   pss_generate(pss_signal, N_id_2);
   sss_generate(sss_signal0, sss_signal5, cell.id);
   
+  //refsignal_cs_generate(&csr_signal, cell);
+
   /* Generate CRS signals */
-  refsignal_cs_generate(&csr_signal, cell);
+  if (chest_dl_init(&est, cell)) {
+    fprintf(stderr, "Error initializing equalizer\n");
+    exit(-1);
+  }
 
-  cell.phich_length = PHICH_NORM;
-  cell.phich_resources = R_1;
-  sfn = 0;
 
   for (i = 0; i < MAX_PORTS; i++) { // now there's only 1 port
     sf_symbols[i] = sf_buffer;
@@ -325,9 +332,6 @@ int main(int argc, char **argv) {
     exit(-1);
   }
 
-  bcch_bch_pack(&cell, 0, bch_payload_packed, BCH_PAYLOAD_LEN/8);
-  bit_pack_vector(bch_payload_packed, bch_payload, BCH_PAYLOAD_LEN);
-
   while (nf < nof_frames || nof_frames == -1) {
     for (sf_idx = 0; sf_idx < NSUBFRAMES_X_FRAME && (nf < nof_frames || nof_frames == -1); sf_idx++) {
       bzero(sf_buffer, sizeof(cf_t) * sf_n_re);
@@ -337,13 +341,14 @@ int main(int argc, char **argv) {
         sss_put_slot(sf_idx ? sss_signal5 : sss_signal0, sf_buffer, cell.nof_prb,
             CPNORM);
       }
+      refsignal_cs_put_sf(cell, 0, est.csr_signal.pilots[0][sf_idx], sf_buffer);
       
       bcch_bch_pack(&cell, sfn, bch_payload_packed, BCH_PAYLOAD_LEN/8);
+      bit_pack_vector(bch_payload_packed, bch_payload, BCH_PAYLOAD_LEN);
       if (sf_idx == 0) {
         pbch_encode(&pbch, bch_payload, sf_symbols);
       }
     
-      refsignal_cs_put_sf(cell, 0, csr_signal.pilots[0][sf_idx], sf_buffer);
 
       pcfich_encode(&pcfich, cfi, sf_symbols, sf_idx);       
 

lte/examples/pdsch_ue.c

@@ -207,9 +207,7 @@ int main(int argc, char **argv) {
     exit(-1);
   }
 
-  pdsch_set_rnti(&ue_dl.pdsch, prog_args.rnti); // This is the RNTI we want to look for
+  pdsch_set_rnti(&ue_dl.pdsch, prog_args.rnti);
-
-
 
   /* Initialize subframe counter */
   sf_cnt = 0;
@@ -301,7 +299,7 @@ int main(int argc, char **argv) {
 #include "liblte/graphics/plot.h"
 plot_real_t poutfft;
 plot_real_t pce;
-plot_scatter_t pscatrecv, pscatequal;
+plot_scatter_t pscatrecv, pscatequal, pscatequal_pdcch;
 
 float tmp_plot[SLOT_LEN_RE(MAX_PRB, CPNORM)];
 float tmp_plot2[SLOT_LEN_RE(MAX_PRB, CPNORM)];
@@ -324,9 +322,15 @@ void init_plots() {
   plot_scatter_setYAxisScale(&pscatrecv, -4, 4);
 
   plot_scatter_init(&pscatequal);
-  plot_scatter_setTitle(&pscatequal, "Equalized Symbols");
+  plot_scatter_setTitle(&pscatequal, "PDSCH - Equalized Symbols");
   plot_scatter_setXAxisScale(&pscatequal, -2, 2);
   plot_scatter_setYAxisScale(&pscatequal, -2, 2);
+
+  plot_scatter_init(&pscatequal_pdcch);
+  plot_scatter_setTitle(&pscatequal_pdcch, "PDCCH - Equalized Symbols");
+  plot_scatter_setXAxisScale(&pscatequal_pdcch, -2, 2);
+  plot_scatter_setYAxisScale(&pscatequal_pdcch, -2, 2);
+
 }
 
 void do_plots(ue_dl_t *q, uint32_t sf_idx) {
@@ -349,6 +353,7 @@ void do_plots(ue_dl_t *q, uint32_t sf_idx) {
   plot_real_setNewData(&pce, tmp_plot2, REFSIGNAL_NUM_SF(q->cell.nof_prb,0));        
   plot_scatter_setNewData(&pscatrecv, q->pdsch.pdsch_symbols[0], nof_symbols);
   plot_scatter_setNewData(&pscatequal, q->pdsch.pdsch_d, nof_symbols);
+  plot_scatter_setNewData(&pscatequal_pdcch, q->pdcch.pdcch_d, 36*q->pdcch.nof_cce);
 }
 
 #endif

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

@@ -58,6 +58,7 @@
 
 #define MIB_MAX_PORTS            4
 #define MIB_FRAME_SIZE_SEARCH   9600
+#define MIB_FFT_SIZE            128
 
 #define MIB_FRAME_UNALIGNED     -3
 #define MIB_FOUND                1
@@ -69,6 +70,7 @@ typedef struct LIBLTE_API {
   cf_t *sf_symbols;
   cf_t *ce[MIB_MAX_PORTS];
   
+  cfo_t cfocorr; 
   lte_fft_t fft;
   chest_dl_t chest; 
   pbch_t pbch;

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

@@ -210,7 +210,7 @@ int refsignal_cs_put_sf(lte_cell_t cell, uint32_t port_id, cf_t *pilots, cf_t *s
       fidx = ((refsignal_cs_v(port_id, l) + (cell.id % 6)) % 6); 
       for (i = 0; i < 2*cell.nof_prb; i++) {
         sf_symbols[SAMPLE_IDX(cell.nof_prb, nsymbol, fidx)] = pilots[REFSIGNAL_PILOT_IDX(i,l,cell)];
-        fidx += 6;       // 1 reference every 6 RE        
+        fidx += RE_X_RB/2;       // 1 reference every 6 RE        
       }    
     }
     return LIBLTE_SUCCESS;      

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

@@ -174,8 +174,6 @@ int ue_dl_decode(ue_dl_t *q, cf_t *input, uint8_t *data, uint32_t sf_idx, uint32
   /* Get channel estimates for each port */
   chest_dl_estimate(&q->chest, q->sf_symbols, q->ce, sf_idx);
   
-  
-  
   /* First decode PCFICH and obtain CFI */
   if (pcfich_decode(&q->pcfich, q->sf_symbols, q->ce, 
                     chest_dl_get_noise_estimate(&q->chest), sf_idx, &cfi, &cfi_distance)<0) {
@@ -240,7 +238,6 @@ int ue_dl_decode(ue_dl_t *q, cf_t *input, uint8_t *data, uint32_t sf_idx, uint32
       }
     }
     if (q->harq_process[0].mcs.mod > 0) {
-
       ret = pdsch_decode(&q->pdsch, q->sf_symbols, q->ce, chest_dl_get_noise_estimate(&q->chest), data, sf_idx, 
           &q->harq_process[0], rvidx);
       if (ret == LIBLTE_ERROR) {

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

@@ -90,6 +90,12 @@ int ue_mib_init(ue_mib_t * q,
       sync_set_cp(&q->sfind, cell.cp);
     }
     
+    if (cfo_init(&q->cfocorr, 5*SF_LEN_PRB(cell.nof_prb))) {
+      fprintf(stderr, "Error initiating CFO\n");
+      goto clean_exit;
+    }
+
+    
     if (lte_fft_init(&q->fft, cell.cp, cell.nof_prb)) {
       fprintf(stderr, "Error initializing FFT\n");
       goto clean_exit;
@@ -124,6 +130,7 @@ void ue_mib_free(ue_mib_t * q)
       free(q->ce[i]);
     }
   }
+  cfo_free(&q->cfocorr);
   sync_free(&q->sfind);
   chest_dl_free(&q->chest);
   pbch_free(&q->pbch);
@@ -161,6 +168,7 @@ int ue_mib_decode_aligned_frame(ue_mib_t * q, cf_t *input,
   if (ret < 0) {
     return LIBLTE_ERROR;
   }
+    
   INFO("Channel estimated for %d ports, Noise: %f\n", q->chest.cell.nof_ports,
        chest_dl_get_noise_estimate(&q->chest));
   /* Reset decoder if we missed a frame */
@@ -253,6 +261,13 @@ int ue_mib_sync_and_decode(ue_mib_t * q,
                 nf*MIB_FRAME_SIZE_SEARCH + peak_idx                             >  MIB_FRAME_SIZE_SEARCH/10)
             {
               // PSS and SSS detected and we have space to decode the PBCH. 
+              
+              // Apply CFO correction 
+              INFO("Correcting CFO: %f\n", sync_get_cfo(&q->sfind));
+              cfo_correct(&q->cfocorr, &signal[nf*MIB_FRAME_SIZE_SEARCH], &signal[nf*MIB_FRAME_SIZE_SEARCH], 
+                          -sync_get_cfo(&q->sfind) / MIB_FFT_SIZE);         
+
+              
               INFO("Trying to decode PBCH\n",0);
               ret = ue_mib_decode_aligned_frame(q, 
                                                 &signal[nf*MIB_FRAME_SIZE_SEARCH+peak_idx-MIB_FRAME_SIZE_SEARCH/10], 

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

@@ -338,7 +338,7 @@ int ue_sync_get_buffer(ue_sync_t *q, cf_t **sf_symbols) {
         }
         
         /* Do CFO Correction and deliver the frame */
-        cfo_correct(&q->cfocorr, q->input_buffer, q->input_buffer, q->cur_cfo / CURRENT_FFTSIZE);         
+        cfo_correct(&q->cfocorr, q->input_buffer, q->input_buffer, -q->cur_cfo / CURRENT_FFTSIZE);         
         *sf_symbols = q->input_buffer;
         
       break;

lte/rrc/lib/messages/src/bcch.c

@@ -97,7 +97,6 @@ int bcch_bch_pack(lte_cell_t *cell, uint32_t sfn, uint8_t *buffer, uint32_t buff
     printf("Failed to encode element %s\n", n.failed_type ? n.failed_type->name : "");
     return LIBLTE_ERROR;
   } 
-
   return LIBLTE_SUCCESS;
 }
 
@@ -131,6 +130,9 @@ int bcch_bch_unpack(uint8_t *buffer, uint32_t msg_nof_bits, lte_cell_t *cell, ui
     case MasterInformationBlock__dl_Bandwidth_n75:
       cell->nof_prb = 75;
       break;
+    case MasterInformationBlock__dl_Bandwidth_n100:
+      cell->nof_prb = 100;
+      break;
   } 
   if (req->phich_Config.phich_Duration == PHICH_Config__phich_Duration_normal) {
     cell->phich_length = PHICH_NORM;    
@@ -155,6 +157,8 @@ int bcch_bch_unpack(uint8_t *buffer, uint32_t msg_nof_bits, lte_cell_t *cell, ui
   memcpy(&sfn_i, req->systemFrameNumber.buf, req->systemFrameNumber.size);
   if (sfn) {
     *sfn=(sfn_i<<2);    
+  } else {
+      asn_fprint(stdout, &asn_DEF_MasterInformationBlock, req); 
   }
   return LIBLTE_SUCCESS;
 }