start_rx_stream delays the start to avoid filling buffers. Started adapting pdsch_ue to 2 antennas

srslte/examples/pdsch_ue.c

@@ -89,6 +89,7 @@ typedef struct {
   uint32_t file_nof_ports;
   uint32_t file_cell_id;
   char *rf_args; 
+  uint32_t rf_nof_rx_ant; 
   double rf_freq; 
   float rf_gain;
   int net_port; 
@@ -113,6 +114,7 @@ void args_default(prog_args_t *args) {
   args->file_offset_freq = 0; 
   args->rf_args = "";
   args->rf_freq = -1.0;
+  args->rf_nof_rx_ant = 1; 
 #ifdef ENABLE_AGC_DEFAULT
   args->rf_gain = -1.0; 
 #else
@@ -163,7 +165,7 @@ 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, "aoglipPcOCtdDnvrfuUsS")) != -1) {
+  while ((opt = getopt(argc, argv, "aAoglipPcOCtdDnvrfuUsS")) != -1) {
     switch (opt) {
     case 'i':
       args->input_file_name = argv[optind];
@@ -186,6 +188,9 @@ void parse_args(prog_args_t *args, int argc, char **argv) {
     case 'a':
       args->rf_args = argv[optind];
       break;
+    case 'A':
+      args->rf_nof_rx_ant = atoi(argv[optind]);
+      break;
     case 'g':
       args->rf_gain = atof(argv[optind]);
       break;
@@ -252,10 +257,13 @@ void sig_int_handler(int signo)
   }
 }
 
+cf_t *sf_buffer[2] = {NULL, NULL}; 
+
 #ifndef DISABLE_RF
 int srslte_rf_recv_wrapper(void *h, void *data, uint32_t nsamples, srslte_timestamp_t *t) {
   DEBUG(" ----  Receive %d samples  ---- \n", nsamples);
-  return srslte_rf_recv(h, data, nsamples, 1);
+  void *d[2] = {data, sf_buffer[1]}; 
+  return srslte_rf_recv_with_time_multi(h, d, nsamples, true, NULL, NULL);
 }
 
 double srslte_rf_set_rx_gain_th_wrapper_(void *h, double f) {
@@ -273,7 +281,6 @@ srslte_ue_sync_t ue_sync;
 prog_args_t prog_args; 
 
 uint32_t sfn = 0; // system frame number
-cf_t *sf_buffer = NULL; 
 srslte_netsink_t net_sink, net_sink_signal; 
 
 int main(int argc, char **argv) {
@@ -311,8 +318,8 @@ int main(int argc, char **argv) {
 #ifndef DISABLE_RF
   if (!prog_args.input_file_name) {
     
-    printf("Opening RF device...\n");
-    if (srslte_rf_open(&rf, prog_args.rf_args)) {
+    printf("Opening RF device with %d RX antennas...\n", prog_args.rf_nof_rx_ant);
+    if (srslte_rf_open_multi(&rf, prog_args.rf_args, prog_args.rf_nof_rx_ant)) {
       fprintf(stderr, "Error opening rf\n");
       exit(-1);
     }
@@ -356,6 +363,10 @@ int main(int argc, char **argv) {
     if (go_exit) {
       exit(0);
     }
+
+    srslte_rf_stop_rx_stream(&rf);
+    srslte_rf_flush_buffer(&rf);    
+
     /* set sampling frequency */
     int srate = srslte_sampling_freq_hz(cell.nof_prb);    
     if (srate != -1) {  
@@ -375,9 +386,7 @@ int main(int argc, char **argv) {
       exit(-1);
     }
 
-    INFO("Stopping RF and flushing buffer...\r",0);
-    srslte_rf_stop_rx_stream(&rf);
-    srslte_rf_flush_buffer(&rf);    
+    printf("Stopping RF and flushing buffer...\r",0);
   }
 #endif
   
@@ -416,6 +425,10 @@ int main(int argc, char **argv) {
     exit(-1);
   }
   
+  for (int i=0;i<prog_args.rf_nof_rx_ant;i++) {
+    sf_buffer[i] = srslte_vec_malloc(3*sizeof(cf_t)*SRSLTE_SF_LEN_PRB(cell.nof_prb));
+  }
+  
   /* Configure downlink receiver for the SI-RNTI since will be the only one we'll use */
   srslte_ue_dl_set_rnti(&ue_dl, prog_args.rnti); 
   
@@ -458,11 +471,11 @@ int main(int argc, char **argv) {
   
   srslte_pbch_decode_reset(&ue_mib.pbch);
             
-  INFO("\nEntering main loop...\n\n", 0);
+  printf("\nEntering main loop...\n\n", 0);
   /* Main loop */
   while (!go_exit && (sf_cnt < prog_args.nof_subframes || prog_args.nof_subframes == -1)) {
     
-    ret = srslte_ue_sync_get_buffer(&ue_sync, &sf_buffer);
+    ret = srslte_ue_sync_zerocopy(&ue_sync, sf_buffer[0]);
     if (ret < 0) {
       fprintf(stderr, "Error calling srslte_ue_sync_work()\n");
     }
@@ -477,7 +490,7 @@ int main(int argc, char **argv) {
       switch (state) {
         case DECODE_MIB:
           if (srslte_ue_sync_get_sfidx(&ue_sync) == 0) {
-            n = srslte_ue_mib_decode(&ue_mib, sf_buffer, bch_payload, NULL, &sfn_offset);
+            n = srslte_ue_mib_decode(&ue_mib, sf_buffer[0], bch_payload, NULL, &sfn_offset);
             if (n < 0) {
               fprintf(stderr, "Error decoding UE MIB\n");
               exit(-1);
@@ -504,7 +517,7 @@ int main(int argc, char **argv) {
           if (decode_pdsch) {            
             INFO("Attempting DL decode SFN=%d\n", sfn);
             n = srslte_ue_dl_decode(&ue_dl, 
-                                    &sf_buffer[prog_args.time_offset], 
+                                    sf_buffer[0], 
                                     data, 
                                     sfn*10+srslte_ue_sync_get_sfidx(&ue_sync));
           

srslte/include/srslte/rf/rf.h

@@ -71,7 +71,15 @@ typedef void (*srslte_rf_error_handler_t)(srslte_rf_error_t error);
 SRSLTE_API int srslte_rf_open(srslte_rf_t *h, 
                        char *args);
 
+SRSLTE_API int srslte_rf_open_multi(srslte_rf_t *h, 
+                                    char *args, 
+                                    uint32_t nof_rx_antennas); 
+
 SRSLTE_API int srslte_rf_open_devname(srslte_rf_t *h, 
+                                      char *devname, 
+                                      char *args);
+
+SRSLTE_API int srslte_rf_open_devname_multi(srslte_rf_t *h, 
                                             char *devname, 
                                             char *args, 
                                             uint32_t nof_rx_antennas);

srslte/lib/rf/rf_imp.c

@@ -98,7 +98,11 @@ const char* srslte_rf_get_devname(srslte_rf_t *rf) {
   return ((rf_dev_t*) rf->dev)->name;
 }
 
-int srslte_rf_open_devname(srslte_rf_t *rf, char *devname, char *args, uint32_t nof_rx_antennas) {
+int srslte_rf_open_devname(srslte_rf_t *rf, char *devname, char *args) {
+  return srslte_rf_open_devname_multi(rf, devname, args, 1);
+}
+
+int srslte_rf_open_devname_multi(srslte_rf_t *rf, char *devname, char *args, uint32_t nof_rx_antennas) {
   /* Try to open the device if name is provided */
   if (devname) {
     if (devname[0] != '\0') {
@@ -117,7 +121,7 @@ int srslte_rf_open_devname(srslte_rf_t *rf, char *devname, char *args, uint32_t
   /* If in auto mode or provided device not found, try to open in order of apperance in available_devices[] array */
   int i=0;
   while(available_devices[i] != NULL) {
-    if (!available_devices[i]->srslte_rf_open(args, &rf->handler)) {
+    if (!available_devices[i]->srslte_rf_open_multi(args, &rf->handler, nof_rx_antennas)) {
       rf->dev = available_devices[i];
       return 0; 
     }
@@ -182,12 +186,12 @@ void srslte_rf_register_error_handler(srslte_rf_t *rf, srslte_rf_error_handler_t
 
 int srslte_rf_open(srslte_rf_t *h, char *args) 
 {
-  return srslte_rf_open_devname(h, NULL, args, 1);
+  return srslte_rf_open_devname_multi(h, NULL, args, 1);
 }
 
 int srslte_rf_open_multi(srslte_rf_t *h, char *args, uint32_t nof_rx_antennas) 
 {
-  return srslte_rf_open_devname(h, NULL, args, nof_rx_antennas);
+  return srslte_rf_open_devname_multi(h, NULL, args, nof_rx_antennas);
 }
 
 int srslte_rf_close(srslte_rf_t *rf)

srslte/lib/rf/rf_uhd_imp.c

@@ -177,10 +177,17 @@ void rf_uhd_set_rx_cal(void *h, srslte_rf_cal_t *cal)
 int rf_uhd_start_rx_stream(void *h)
 {
   rf_uhd_handler_t *handler = (rf_uhd_handler_t*) h;
+
   uhd_stream_cmd_t stream_cmd = {
         .stream_mode = UHD_STREAM_MODE_START_CONTINUOUS,
-        .stream_now = true
+        .stream_now = false
   };
+  uhd_usrp_get_time_now(handler->usrp, 0, &stream_cmd.time_spec_full_secs, &stream_cmd.time_spec_frac_secs);
+  stream_cmd.time_spec_frac_secs += 0.5; 
+  if (stream_cmd.time_spec_frac_secs > 1) {
+    stream_cmd.time_spec_frac_secs -= 1;
+    stream_cmd.time_spec_full_secs += 1; 
+  }
   uhd_rx_streamer_issue_stream_cmd(handler->rx_stream, &stream_cmd);
   return 0;
 }
@@ -199,9 +206,11 @@ int rf_uhd_stop_rx_stream(void *h)
 void rf_uhd_flush_buffer(void *h)
 {
   int n; 
-  cf_t tmp[1024];
+  cf_t tmp1[1024];
+  cf_t tmp2[1024];
+  void *data[2] = {tmp1, tmp2};
   do {
-    n = rf_uhd_recv_with_time(h, tmp, 1024, 0, NULL, NULL);
+    n = rf_uhd_recv_with_time_multi(h, data, 1024, 0, NULL, NULL);
   } while (n > 0);  
 }
 
@@ -505,6 +514,9 @@ int rf_uhd_recv_with_time(void *h,
   return rf_uhd_recv_with_time_multi(h, &data, nsamples, blocking, secs, frac_secs);
 }
 
+cf_t data1[1024*100];
+cf_t data2[1024*100];
+
 int rf_uhd_recv_with_time_multi(void *h,
                                 void **data,
                                 uint32_t nsamples,
@@ -514,13 +526,13 @@ int rf_uhd_recv_with_time_multi(void *h,
 {
   
   rf_uhd_handler_t *handler = (rf_uhd_handler_t*) h;
-  size_t rxd_samples[4];
+  size_t rxd_samples;
   uhd_rx_metadata_handle *md = &handler->rx_md_first; 
   int trials = 0; 
   if (blocking) {
     int n = 0;
     do {
-      size_t rx_samples = handler->rx_nof_samples;
+      size_t rx_samples = nsamples;
              
       if (rx_samples > nsamples - n) {
         rx_samples = nsamples - n; 
@@ -530,20 +542,20 @@ int rf_uhd_recv_with_time_multi(void *h,
         cf_t *data_c = (cf_t*) data[i];
         buffs_ptr[i] = &data_c[n];        
       }
-      uhd_error error = uhd_rx_streamer_recv(handler->rx_stream, buffs_ptr, 
-                                             rx_samples, md, 1.0, false, rxd_samples);
 
+      uhd_error error = uhd_rx_streamer_recv(handler->rx_stream, buffs_ptr, 
+                                             rx_samples, md, 1.0, false, &rxd_samples);
       if (error) {
         fprintf(stderr, "Error receiving from UHD: %d\n", error);
         return -1; 
       }
       md = &handler->rx_md; 
-      n += rxd_samples[0];
+      n += rxd_samples;
       trials++;
     } while (n < nsamples && trials < 100);
   } else {
     return uhd_rx_streamer_recv(handler->rx_stream, data, 
-                                             nsamples, md, 0.0, false, rxd_samples);
+                                nsamples, md, 0.0, false, &rxd_samples);
   }
   if (secs && frac_secs) {
     uhd_rx_metadata_time_spec(handler->rx_md_first, secs, frac_secs);

srslte/lib/rf/rf_utils.c

@@ -82,10 +82,11 @@ free_and_exit:
   return ret;
 }
 
-
+cf_t data2[1920*160];
 int srslte_rf_recv_wrapper_cs(void *h, void *data, uint32_t nsamples, srslte_timestamp_t *t) {
   DEBUG(" ----  Receive %d samples  ---- \n", nsamples);
-  return srslte_rf_recv(h, data, nsamples, 1);
+  void *d[2] = {data, data2}; 
+  return srslte_rf_recv_with_time_multi(h, d, nsamples, 1, NULL, NULL);
 }
 
 double srslte_rf_set_rx_gain_th_wrapper(void *h, double f) {