Adjust samples in time only when valid PBCH is present

executables/nr-ue.c

@@ -734,16 +734,6 @@ void syncInFrame(PHY_VARS_NR_UE *UE, openair0_timestamp *timestamp) {
     }
 }
 
-int computeSamplesShift(PHY_VARS_NR_UE *UE) {
-  int samples_shift = -(UE->rx_offset>>1);
-  if (samples_shift != 0) {
-    LOG_I(NR_PHY,"Adjusting frame in time by %i samples\n", samples_shift);
-    UE->rx_offset = 0; // reset so that it is not applied falsely in case of SSB being only in every second frame
-    UE->max_pos_fil += samples_shift << 15; // reset IIR filter when sample shift is applied
-  }
-  return samples_shift;
-}
-
 static inline int get_firstSymSamp(uint16_t slot, NR_DL_FRAME_PARMS *fp) {
   if (fp->numerology_index == 0)
     return fp->nb_prefix_samples0 + fp->ofdm_symbol_size;
@@ -904,14 +894,13 @@ void *UE_thread(void *arg) {
 
     int readBlockSize, writeBlockSize;
 
-    if (slot_nr<(nb_slot_frame - 1)) {
-      readBlockSize=get_readBlockSize(slot_nr, &UE->frame_parms);
-      writeBlockSize=UE->frame_parms.get_samples_per_slot((slot_nr + DURATION_RX_TO_TX) % nb_slot_frame, &UE->frame_parms);
-    } else {
-      UE->rx_offset_diff = computeSamplesShift(UE);
-      readBlockSize=get_readBlockSize(slot_nr, &UE->frame_parms) -
-                    UE->rx_offset_diff;
-      writeBlockSize=UE->frame_parms.get_samples_per_slot((slot_nr + DURATION_RX_TO_TX) % nb_slot_frame, &UE->frame_parms)- UE->rx_offset_diff;
+    readBlockSize=get_readBlockSize(slot_nr, &UE->frame_parms);
+    writeBlockSize=UE->frame_parms.get_samples_per_slot((slot_nr + DURATION_RX_TO_TX) % nb_slot_frame, &UE->frame_parms);
+    if (UE->apply_timing_offset && (slot_nr == nb_slot_frame-1)) {
+      const int sampShift = -(UE->rx_offset>>1);
+      readBlockSize  -= sampShift;
+      writeBlockSize -= sampShift;
+      UE->apply_timing_offset = false;
     }
 
     AssertFatal(readBlockSize ==

openair1/PHY/NR_UE_ESTIMATION/nr_adjust_synch_ue.c

@@ -94,6 +94,10 @@ void nr_adjust_synch_ue(NR_DL_FRAME_PARMS *frame_parms,
   else
     ue->rx_offset = diff;
 
+  const int sample_shift = -(ue->rx_offset>>1);
+  // reset IIR filter for next offset calculation
+  ue->max_pos_fil += sample_shift << 15;
+
   if(abs(diff)<5)
     count_max_pos_ok ++;
   else

openair1/PHY/NR_UE_TRANSPORT/nr_dlsch_decoding.c

@@ -284,7 +284,7 @@ void nr_processDLSegment(void* arg) {
       if (no_iteration_ldpc > dlsch->max_ldpc_iterations)
         no_iteration_ldpc = dlsch->max_ldpc_iterations;
     } else {
-      LOG_I(PHY,"%d.%d CRC NOT OK\n",rdata->proc->frame_rx,rdata->proc->nr_slot_rx);
+      LOG_D(PHY,"%d.%d CRC NOT OK\n",rdata->proc->frame_rx,rdata->proc->nr_slot_rx);
       no_iteration_ldpc = dlsch->max_ldpc_iterations + 1;
     }
 

openair1/PHY/defs_nr_UE.h

@@ -516,6 +516,7 @@ typedef struct {
   int              rx_offset;      /// Timing offset
   int              rx_offset_diff; /// Timing adjustment for ofdm symbol0 on HW USRP
   int              max_pos_fil;    /// Timing offset IIR filter
+  bool             apply_timing_offset;     /// Do time sync for current frame
   int              time_sync_cell;
 
   /// Timing Advance updates variables

openair1/SCHED_NR_UE/phy_procedures_nr_ue.c

@@ -352,12 +352,12 @@ void nr_ue_measurement_procedures(uint16_t l,
   VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_UE_MEASUREMENT_PROCEDURES, VCD_FUNCTION_OUT);
 }
 
-static void nr_ue_pbch_procedures(PHY_VARS_NR_UE *ue,
-                                  UE_nr_rxtx_proc_t *proc,
-                                  int estimateSz,
-                                  struct complex16 dl_ch_estimates[][estimateSz],
-                                  nr_phy_data_t *phy_data,
-                                  c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP]) {
+static int nr_ue_pbch_procedures(PHY_VARS_NR_UE *ue,
+                                 UE_nr_rxtx_proc_t *proc,
+                                 int estimateSz,
+                                 struct complex16 dl_ch_estimates[][estimateSz],
+                                 nr_phy_data_t *phy_data,
+                                 c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP]) {
 
   int ret = 0;
   DevAssert(ue);
@@ -420,6 +420,7 @@ static void nr_ue_pbch_procedures(PHY_VARS_NR_UE *ue,
 
   }
 
+ return ret;
 
   VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_UE_PBCH_PROCEDURES, VCD_FUNCTION_OUT);
 }
@@ -929,9 +930,9 @@ void pbch_pdcch_processing(PHY_VARS_NR_UE *ue,
           if(ssb_index == fp->ssb_index) {
 
             LOG_D(PHY," ------  Decode MIB: frame.slot %d.%d ------  \n", frame_rx%1024, nr_slot_rx);
-            nr_ue_pbch_procedures(ue, proc, estimateSz, dl_ch_estimates, phy_data, rxdataF);
+            const int pbchSuccess = nr_ue_pbch_procedures(ue, proc, estimateSz, dl_ch_estimates, phy_data, rxdataF);
 
-            if (ue->no_timing_correction==0) {
+            if (ue->no_timing_correction==0 && pbchSuccess == 0) {
               LOG_D(PHY,"start adjust sync slot = %d no timing %d\n", nr_slot_rx, ue->no_timing_correction);
               nr_adjust_synch_ue(fp,
                                  ue,
@@ -943,6 +944,7 @@ void pbch_pdcch_processing(PHY_VARS_NR_UE *ue,
                                  0,
                                  16384);
             }
+            ue->apply_timing_offset = true;
           }
           LOG_D(PHY, "Doing N0 measurements in %s\n", __FUNCTION__);
           nr_ue_rrc_measurements(ue, proc, rxdataF);