NR_UE: reset max_pos_fil in timing synchronization whenever we add/remove a sample

executables/nr-ue.c

@@ -464,14 +464,16 @@ int computeSamplesShift(PHY_VARS_NR_UE *UE) {
   if ( UE->rx_offset < UE->frame_parms.samples_per_frame/2  &&
        UE->rx_offset > 0 ) {
     //LOG_I(PHY,"!!!adjusting -1 samples!!!\n");
-    UE->rx_offset = 0; // reset so that it is not applied falsely in case of SSB being only in every second frame
+    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 = 0; // reset IIR filter when sample shift is applied
     return -1 ;
   }
 
   if ( UE->rx_offset > UE->frame_parms.samples_per_frame/2 &&
        UE->rx_offset < UE->frame_parms.samples_per_frame ) {
     //LOG_I(PHY,"!!!adjusting +1 samples!!!\n");
-    UE->rx_offset = 0; // reset so that it is not applied falsely in case of SSB being only in every second frame
+    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 = 0; // reset IIR filter when sample shift is applied
     return 1;
   }
 

openair1/PHY/NR_UE_ESTIMATION/nr_adjust_synch_ue.c

@@ -42,7 +42,6 @@ void nr_adjust_synch_ue(NR_DL_FRAME_PARMS *frame_parms,
                         short coef)
 {
 
-  static int max_pos_fil = 0;
   static int count_max_pos_ok = 0;
   static int first_time = 1;
   int max_val = 0, max_pos = 0;
@@ -74,14 +73,14 @@ void nr_adjust_synch_ue(NR_DL_FRAME_PARMS *frame_parms,
 
   // filter position to reduce jitter
   if (clear == 1)
-    max_pos_fil = max_pos;
+    ue->max_pos_fil = max_pos;
   else
-    max_pos_fil = ((max_pos_fil * coef) + (max_pos * ncoef)) >> 15;
+    ue->max_pos_fil = ((ue->max_pos_fil * coef) + (max_pos * ncoef)) >> 15;
 
   // do not filter to have proactive timing adjustment
-  //max_pos_fil = max_pos;
+  //ue->max_pos_fil = max_pos;
 
-  int diff = max_pos_fil - sync_pos;
+  int diff = ue->max_pos_fil - sync_pos;
 
   if (frame_parms->freq_range==nr_FR2) 
     sync_offset = 2;
@@ -129,7 +128,7 @@ void nr_adjust_synch_ue(NR_DL_FRAME_PARMS *frame_parms,
         ue->rx_offset,
         clear,
         max_pos,
-        max_pos_fil,
+        ue->max_pos_fil,
         max_val,
         sync_pos);
 #endif //DEBUG_PHY

openair1/PHY/defs_nr_UE.h

@@ -921,9 +921,10 @@ typedef struct {
   uint8_t               init_sync_frame;
   /// temporary offset during cell search prior to MIB decoding
   int              ssb_offset;
-  uint16_t	   symbol_offset; // offset in terms of symbols for detected ssb in sync
-  int              rx_offset; /// Timing offset
+  uint16_t         symbol_offset;  /// offset in terms of symbols for detected ssb in sync
+  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
   int              time_sync_cell;
 
   /// Timing Advance updates variables