for_review_then_squash

openair1/PHY/NR_REFSIG/nr_dmrs_rx.c

@@ -202,7 +202,7 @@ int nr_pdcch_dmrs_rx(PHY_VARS_NR_UE *ue,
   return(0);
 }
 
-int nr_pbch_dmrs_rx(int symbol, unsigned int *nr_gold_pbch, c16_t *output)
+void nr_pbch_dmrs_rx(const int symbol, const unsigned int *nr_gold_pbch, c16_t *output)
 {
   int m,m0,m1;
   uint8_t idx=0;
@@ -232,8 +232,6 @@ int nr_pbch_dmrs_rx(int symbol, unsigned int *nr_gold_pbch, c16_t *output)
       }
 #endif
   }
-  
-  return(0);
 }
 
 /*!

openair1/PHY/NR_REFSIG/refsig_defs_ue.h

@@ -30,7 +30,7 @@
 /*!\brief This function generates the NR Gold sequence (38-211, Sec 5.2.1) for the PBCH DMRS.
 @param PHY_VARS_NR_UE* ue structure provides configuration, frame parameters and the pointers to the 32 bits sequence storage tables
  */
-int nr_pbch_dmrs_rx(int dmrss, unsigned int *nr_gold_pbch, c16_t *output);
+void nr_pbch_dmrs_rx(const int dmrss, const unsigned int *nr_gold_pbch, c16_t *output);
 
 /*!\brief This function generates the NR Gold sequence (38-211, Sec 5.2.1) for the PDCCH DMRS.
 @param PHY_VARS_NR_UE* ue structure provides configuration, frame parameters and the pointers to the 32 bits sequence storage tables

openair1/PHY/NR_UE_ESTIMATION/nr_dl_channel_estimation.c

@@ -631,28 +631,19 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
   return(0);
 }
 
-int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
+c32_t nr_pbch_dmrs_correlation(const PHY_VARS_NR_UE *ue,
                                const UE_nr_rxtx_proc_t *proc,
-                             unsigned char symbol,
-                             int dmrss,
-                             NR_UE_SSB *current_ssb,
-                             c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP])
+                               const int symbol,
+                               const int dmrss,
+                               const uint32_t nr_gold_pbch[NR_PBCH_DMRS_LENGTH_DWORD],
+                               const c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP])
 {
-  c16_t pilot[200] __attribute__((aligned(16)));
-  unsigned int pilot_cnt;
-  int symbol_offset;
-
-  uint8_t ssb_index=current_ssb->i_ssb;
-  uint8_t n_hf=current_ssb->n_hf;
+  AssertFatal(dmrss >= 0 && dmrss < 3, "symbol %d is illegal for PBCH DM-RS \n", dmrss);
 
   unsigned int  ssb_offset = ue->frame_parms.first_carrier_offset + ue->frame_parms.ssb_start_subcarrier;
   if (ssb_offset>= ue->frame_parms.ofdm_symbol_size) ssb_offset-=ue->frame_parms.ofdm_symbol_size;
 
-  AssertFatal(dmrss >= 0 && dmrss < 3,
-	      "symbol %d is illegal for PBCH DM-RS \n",
-	      dmrss);
-
-  symbol_offset = ue->frame_parms.ofdm_symbol_size*symbol;
+  int symbol_offset = ue->frame_parms.ofdm_symbol_size * symbol;
 
   unsigned int k = ue->frame_parms.Nid_cell % 4;
 
@@ -665,64 +656,64 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
 
   // generate pilot
   // Note: pilot returned by the following function is already the complex conjugate of the transmitted DMRS
-  nr_pbch_dmrs_rx(dmrss, ue->nr_gold_pbch[n_hf][ssb_index], pilot);
-
+  c16_t pilot[200] __attribute__((aligned(16)));
+  nr_pbch_dmrs_rx(dmrss, nr_gold_pbch, pilot);
+  c32_t computed_val = {0};
   for (int aarx=0; aarx<ue->frame_parms.nb_antennas_rx; aarx++) {
 
     int re_offset = ssb_offset;
     c16_t *pil = pilot;
-    c16_t *rxF = &rxdataF[aarx][symbol_offset + k];
+    const c16_t *rxF = &rxdataF[aarx][symbol_offset + k];
 
     DEBUG_PBCH("pbch ch est pilot RB_DL %d\n", ue->frame_parms.N_RB_DL);
     DEBUG_PBCH("k %d, first_carrier %d\n", k, ue->frame_parms.first_carrier_offset);
-    //if ((ue->frame_parms.N_RB_DL&1)==0) {
 
     // Treat first 2 pilots specially (left edge)
-    current_ssb->c = c32x16maddShift(*pil, rxF[re_offset], current_ssb->c, 15);
+    computed_val = c32x16maddShift(*pil, rxF[re_offset], computed_val, 15);
 
     DEBUG_PBCH("ch 0 %d\n", pil->r * rxF[re_offset].r - pil->i * rxF[re_offset].i);
     DEBUG_PBCH("pilot 0 : rxF - > (%d,%d)  pil -> (%d,%d) \n", rxF[re_offset].r, rxF[re_offset].i, pil->r, pil->i);
 
     pil++;
     re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
-    current_ssb->c = c32x16maddShift(*pil, rxF[re_offset], current_ssb->c, 15);
+    computed_val = c32x16maddShift(*pil, rxF[re_offset], computed_val, 15);
 
     DEBUG_PBCH("pilot 1 : rxF - > (%d,%d)  pil -> (%d,%d) \n", rxF[re_offset].r, rxF[re_offset].i, pil->r, pil->i);
 
     pil++;
     re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
-    current_ssb->c = c32x16maddShift(*pil, rxF[re_offset], current_ssb->c, 15);
+    computed_val = c32x16maddShift(*pil, rxF[re_offset], computed_val, 15);
 
     DEBUG_PBCH("pilot 2 : rxF - > (%d,%d), pil -> (%d,%d) \n", rxF[re_offset].r, rxF[re_offset].i, pil->r, pil->i);
 
     pil++;
     re_offset = (re_offset + 4) % ue->frame_parms.ofdm_symbol_size;
 
-    for (pilot_cnt = 3; pilot_cnt < (3 * 20); pilot_cnt += 3) {
+    for (int pilot_cnt = 3; pilot_cnt < (3 * 20); pilot_cnt += 3) {
       // in 2nd symbol, skip middle  REs (48 with DMRS,  144 for SSS, and another 48 with DMRS) 
       if (dmrss == 1 && pilot_cnt == 12) {
 	pilot_cnt=48;
   re_offset = (re_offset + 144) % ue->frame_parms.ofdm_symbol_size;
       }
-      current_ssb->c = c32x16maddShift(*pil, rxF[re_offset], current_ssb->c, 15);
+      computed_val = c32x16maddShift(*pil, rxF[re_offset], computed_val, 15);
 
       DEBUG_PBCH("pilot %u : rxF= (%d,%d) pil= (%d,%d) \n", pilot_cnt, rxF[re_offset].r, rxF[re_offset].i, pil->r, pil->i);
 
       pil++;
       re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
-      current_ssb->c = c32x16maddShift(*pil, rxF[re_offset], current_ssb->c, 15);
+      computed_val = c32x16maddShift(*pil, rxF[re_offset], computed_val, 15);
 
       DEBUG_PBCH("pilot %u : rxF= (%d,%d) pil= (%d,%d) \n", pilot_cnt + 1, rxF[re_offset].r, rxF[re_offset].i, pil->r, pil->i);
       pil++;
       re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
-      current_ssb->c = c32x16maddShift(*pil, rxF[re_offset], current_ssb->c, 15);
+      computed_val = c32x16maddShift(*pil, rxF[re_offset], computed_val, 15);
 
       DEBUG_PBCH("pilot %u : rxF= (%d,%d)  pil= (%d,%d) \n", pilot_cnt + 2, rxF[re_offset].r, rxF[re_offset].i, pil->r, pil->i);
       pil++;
       re_offset = (re_offset + 4) % ue->frame_parms.ofdm_symbol_size;
     }
   }
-  return(0);
+  return computed_val;
 }
 
 int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,

openair1/PHY/NR_UE_ESTIMATION/nr_estimation.h

@@ -57,12 +57,12 @@ void nr_pdcch_channel_estimation(PHY_VARS_NR_UE *ue,
                                  c16_t pdcch_dl_ch_estimates[][pdcch_est_size],
                                  c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP]);
 
-int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
+c32_t nr_pbch_dmrs_correlation(const PHY_VARS_NR_UE *ue,
                                const UE_nr_rxtx_proc_t *proc,
-                             unsigned char symbol,
-                             int dmrss,
-                             NR_UE_SSB *current_ssb,
-                             c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP]);
+                               const int symbol,
+                               const int dmrss,
+                               const uint32_t nr_gold_pbch[NR_PBCH_DMRS_LENGTH_DWORD],
+                               const c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP]);
 
 int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
                                int estimateSz,

openair1/PHY/NR_UE_TRANSPORT/nr_initial_sync.c

@@ -44,6 +44,7 @@
 #include "PHY/NR_REFSIG/pss_nr.h"
 #include "PHY/NR_REFSIG/sss_nr.h"
 #include "PHY/NR_REFSIG/refsig_defs_ue.h"
+#include "PHY/TOOLS/tools_defs.h"
 
 //static  nfapi_nr_config_request_t config_t;
 //static  nfapi_nr_config_request_t* config =&config_t;
@@ -52,8 +53,19 @@ int cnt=0;
 // #define DEBUG_INITIAL_SYNCH
 #define DUMP_PBCH_CH_ESTIMATES 0
 
+// structure used for multiple SSB detection
+typedef struct NR_UE_SSB {
+  uint i_ssb; // i_ssb between 0 and 7 (it corresponds to ssb_index only for Lmax=4,8)
+  uint n_hf; // n_hf = 0,1 for Lmax =4 or n_hf = 0 for Lmax =8,64
+  uint32_t metric; // metric to order SSB hypothesis
+} NR_UE_SSB;
 
-int nr_pbch_detection(const UE_nr_rxtx_proc_t *proc,
+static int ssb_sort(const void *a, const void *b)
+{
+  return ((NR_UE_SSB *)b)->metric - ((NR_UE_SSB *)a)->metric;
+}
+
+static bool nr_pbch_detection(const UE_nr_rxtx_proc_t *proc,
                               PHY_VARS_NR_UE *ue,
                               int pbch_initial_symbol,
                               c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP])
@@ -64,54 +76,62 @@ int nr_pbch_detection(const UE_nr_rxtx_proc_t *proc,
   const int N_hf = (frame_parms->Lmax == 4) ? 2 : 1;
   NR_UE_SSB best_ssb[N_L * N_hf];
   NR_UE_SSB *current_ssb = best_ssb;
-  // loops over possible pbch dmrs cases to retrive best estimated i_ssb (and n_hf for Lmax=4) for multiple ssb detection
-  for (int hf = 0; hf < N_hf; hf++) {
-    for (int l = 0; l < N_L ; l++) {
-      // initialization of structure
-      *current_ssb = (NR_UE_SSB){.i_ssb = l, .n_hf = hf};
+  // loops over possible pbch dmrs cases to retrieve best estimated i_ssb (and n_hf for Lmax=4) for multiple ssb detection
   start_meas(&ue->dlsch_channel_estimation_stats);
+  for (int hf = 0; hf < N_hf; hf++) {
+    for (int l = 0; l < N_L; l++) {
       // computing correlation between received DMRS symbols and transmitted sequence for current i_ssb and n_hf
-      for(int i=pbch_initial_symbol; i<pbch_initial_symbol+3;i++)
-        nr_pbch_dmrs_correlation(ue, proc, i, i - pbch_initial_symbol, current_ssb, rxdataF);
-      stop_meas(&ue->dlsch_channel_estimation_stats);
+      c32_t cumul = {0};
+      for (int i = pbch_initial_symbol; i < pbch_initial_symbol + 3; i++) {
+        c32_t meas = nr_pbch_dmrs_correlation(ue, proc, i, i - pbch_initial_symbol, ue->nr_gold_pbch[hf][l], rxdataF);
+        csum(cumul, cumul, meas);
+      }
+      // initialization of structure
+      *current_ssb = (NR_UE_SSB){.i_ssb = l, .n_hf = hf, .metric = squaredMod(cumul)};
       current_ssb++;
     }
   }
+  qsort(best_ssb, N_L * N_hf, sizeof(NR_UE_SSB), ssb_sort);
+  stop_meas(&ue->dlsch_channel_estimation_stats);
 
-  for (NR_UE_SSB *temp_ptr = best_ssb; ret != 0 && temp_ptr < best_ssb + N_L * N_hf; temp_ptr++) {
+  const int nb_ant = frame_parms->nb_antennas_rx;
+  for (NR_UE_SSB *ssb = best_ssb; ssb < best_ssb + N_L * N_hf; ssb++) {
     start_meas(&ue->dlsch_channel_estimation_stats);
     // computing channel estimation for selected best ssb
     const int estimateSz = frame_parms->symbols_per_slot * frame_parms->ofdm_symbol_size;
-    __attribute__ ((aligned(32))) struct complex16 dl_ch_estimates[frame_parms->nb_antennas_rx][estimateSz];
-    __attribute__ ((aligned(32))) struct complex16 dl_ch_estimates_time[frame_parms->nb_antennas_rx][frame_parms->ofdm_symbol_size];
+    __attribute__((aligned(32))) c16_t dl_ch_estimates[nb_ant][estimateSz];
+    __attribute__((aligned(32))) c16_t dl_ch_estimates_time[nb_ant][frame_parms->ofdm_symbol_size];
 
     for(int i=pbch_initial_symbol; i<pbch_initial_symbol+3;i++)
-      nr_pbch_channel_estimation(ue,estimateSz, dl_ch_estimates, dl_ch_estimates_time, 
-                                 proc,i,i-pbch_initial_symbol,temp_ptr->i_ssb,temp_ptr->n_hf,rxdataF);
+      nr_pbch_channel_estimation(ue,
+                                 estimateSz,
+                                 dl_ch_estimates,
+                                 dl_ch_estimates_time,
+                                 proc,
+                                 i,
+                                 i - pbch_initial_symbol,
+                                 ssb->i_ssb,
+                                 ssb->n_hf,
+                                 rxdataF);
 
     stop_meas(&ue->dlsch_channel_estimation_stats);
     fapiPbch_t result = {0};
-
-    int pbch_res = nr_rx_pbch(ue, proc, estimateSz, dl_ch_estimates, frame_parms, temp_ptr->i_ssb, &result, rxdataF);
-    ret = pbch_res == 0;
-
-    if (DUMP_PBCH_CH_ESTIMATES && ret) {
-      write_output("pbch_ch_estimates.m", "pbch_ch_estimates", dl_ch_estimates, frame_parms->nb_antennas_rx*estimateSz, 1, 1);
+    if (0 == nr_rx_pbch(ue, proc, estimateSz, dl_ch_estimates, frame_parms, ssb->i_ssb, &result, rxdataF)) {
+      if (DUMP_PBCH_CH_ESTIMATES) {
+        write_output("pbch_ch_estimates.m", "pbch_ch_estimates", dl_ch_estimates, nb_ant * estimateSz, 1, 1);
         write_output("pbch_ch_estimates_time.m",
                      "pbch_ch_estimates_time",
                      dl_ch_estimates_time,
-                   frame_parms->nb_antennas_rx * frame_parms->ofdm_symbol_size,
+                     nb_ant * frame_parms->ofdm_symbol_size,
                      1,
                      1);
       }
+      return false;
+    }
   }
 
-  if (ret == 0) {
-    LOG_I(PHY, "[UE%d] Initial sync: pbch decoded sucessfully, ssb index %d\n", ue->Mod_id, frame_parms->ssb_index);
-  } else {
   LOG_W(PHY, "[UE%d] Initial sync: pbch not decoded, ssb index %d\n", ue->Mod_id, frame_parms->ssb_index);
-  }
-  return ret;
+  return true;
 }
 
 nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, int n_frames, int sa)

openair1/PHY/defs_nr_UE.h

@@ -307,13 +307,6 @@ typedef struct {
   fapi_nr_ul_config_srs_pdu srs_config_pdu;
 } NR_UE_SRS;
 
-// structure used for multiple SSB detection
-typedef struct NR_UE_SSB {
-  uint8_t i_ssb;   // i_ssb between 0 and 7 (it corresponds to ssb_index only for Lmax=4,8)
-  uint8_t n_hf;    // n_hf = 0,1 for Lmax =4 or n_hf = 0 for Lmax =8,64
-  c32_t c;
-} NR_UE_SSB;
-
 typedef struct UE_NR_SCAN_INFO_s {
   /// 10 best amplitudes (linear) for each pss signals
   int32_t amp[3][10];