added pucch 2ab

srslte/include/srslte/ch_estimation/chest_ul.h

@@ -56,6 +56,7 @@ typedef struct {
   bool dmrs_signal_configured; 
   
   cf_t *pilot_estimates;
+  cf_t *pilot_estimates_tmp[4];
   cf_t *pilot_recv_signal; 
   cf_t *pilot_known_signal; 
   cf_t *tmp_noise; 
@@ -105,7 +106,8 @@ SRSLTE_API int srslte_chest_ul_estimate_pucch(srslte_chest_ul_t *q,
                                               cf_t *ce, 
                                               srslte_pucch_format_t format, 
                                               uint32_t n_pucch, 
-                                              uint32_t sf_idx); 
+                                              uint32_t sf_idx, 
+                                              uint8_t *pucch2_ack_bits); 
 
 SRSLTE_API float srslte_chest_ul_get_noise_estimate(srslte_chest_ul_t *q); 
 

srslte/lib/ch_estimation/chest_ul.c

@@ -78,6 +78,13 @@ int srslte_chest_ul_init(srslte_chest_ul_t *q, srslte_cell_t cell)
       perror("malloc");
       goto clean_exit;
     }      
+    for (int i=0;i<4;i++) {
+      q->pilot_estimates_tmp[i] = srslte_vec_malloc(sizeof(cf_t) * NOF_REFS_SF);
+      if (!q->pilot_estimates_tmp[i]) {
+        perror("malloc");
+        goto clean_exit;
+      }      
+    }
     q->pilot_recv_signal = srslte_vec_malloc(sizeof(cf_t) * (NOF_REFS_SF+1));
     if (!q->pilot_recv_signal) {
       perror("malloc");
@@ -125,6 +132,11 @@ void srslte_chest_ul_free(srslte_chest_ul_t *q)
   if (q->pilot_estimates) {
     free(q->pilot_estimates);
   }      
+  for (int i=0;i<4;i++) {
+    if (q->pilot_estimates_tmp[i]) {
+      free(q->pilot_estimates_tmp[i]);
+    }
+  }
   if (q->pilot_recv_signal) {
     free(q->pilot_recv_signal);
   }
@@ -266,7 +278,8 @@ int srslte_chest_ul_estimate(srslte_chest_ul_t *q, cf_t *input, cf_t *ce,
 }
 
 int srslte_chest_ul_estimate_pucch(srslte_chest_ul_t *q, cf_t *input, cf_t *ce, 
-                                   srslte_pucch_format_t format, uint32_t n_pucch, uint32_t sf_idx) 
+                                   srslte_pucch_format_t format, uint32_t n_pucch, uint32_t sf_idx, 
+                                   uint8_t *pucch2_ack_bits) 
 {
   if (!q->dmrs_signal_configured) {
     fprintf(stderr, "Error must call srslte_chest_ul_set_cfg() before using the UL estimator\n");
@@ -285,11 +298,37 @@ int srslte_chest_ul_estimate_pucch(srslte_chest_ul_t *q, cf_t *input, cf_t *ce,
   
   /* Generate known pilots */
   uint8_t pucch2_bits[2] = {0, 0};
-  srslte_refsignal_dmrs_pucch_gen(&q->dmrs_signal, format, n_pucch, sf_idx, pucch2_bits, q->pilot_known_signal),
+  if (format == SRSLTE_PUCCH_FORMAT_2A || format == SRSLTE_PUCCH_FORMAT_2B) {
+    float max = -1e9;
+    int i_max = 0; 
+    
+    int m = 0; 
+    if (format == SRSLTE_PUCCH_FORMAT_2A) {
+      m = 2; 
+    } else {
+      m = 4; 
+    }
+    
+    for (int i=0;i<m;i++) {
+      pucch2_bits[0] = i%2;
+      pucch2_bits[1] = i/2;
+      srslte_refsignal_dmrs_pucch_gen(&q->dmrs_signal, format, n_pucch, sf_idx, pucch2_bits, q->pilot_known_signal);
+      srslte_vec_prod_conj_ccc(q->pilot_recv_signal, q->pilot_known_signal, q->pilot_estimates_tmp[i], nrefs_sf);
+      float x = cabsf(srslte_vec_acc_cc(q->pilot_estimates_tmp[i], nrefs_sf));
+      if (x >= max) {
+        max = x; 
+        i_max = i; 
+      }      
+    }
+    memcpy(q->pilot_estimates, q->pilot_estimates_tmp[i_max], nrefs_sf*sizeof(cf_t));
+    pucch2_ack_bits[0] = i_max%2;
+    pucch2_ack_bits[1] = i_max/2;
+  } else {
+    srslte_refsignal_dmrs_pucch_gen(&q->dmrs_signal, format, n_pucch, sf_idx, pucch2_bits, q->pilot_known_signal);
+    /* Use the known DMRS signal to compute Least-squares estimates */
+    srslte_vec_prod_conj_ccc(q->pilot_recv_signal, q->pilot_known_signal, q->pilot_estimates, nrefs_sf);
+  }
   
-  /* Use the known DMRS signal to compute Least-squares estimates */
-  srslte_vec_prod_conj_ccc(q->pilot_recv_signal, q->pilot_known_signal, q->pilot_estimates, nrefs_sf);
- 
   if (ce != NULL) {
     /* FIXME: Currently averaging entire slot, performance good enough? */
     for (int ns=0;ns<2;ns++) {

srslte/lib/enb/enb_ul.c

@@ -230,12 +230,11 @@ int get_pucch(srslte_enb_ul_t *q, uint16_t rnti,
     
   uint32_t n_pucch = srslte_pucch_get_npucch(pdcch_n_cce, format, uci_data->scheduling_request, &q->users[rnti]->pucch_sched);
   
-  if (srslte_chest_ul_estimate_pucch(&q->chest, q->sf_symbols, q->ce, format, n_pucch, sf_rx)) {
+  if (srslte_chest_ul_estimate_pucch(&q->chest, q->sf_symbols, q->ce, format, n_pucch, sf_rx, &bits[20])) {
     fprintf(stderr,"Error estimating PUCCH DMRS\n");
     return SRSLTE_ERROR;
   }
   
-  
   int ret_val = srslte_pucch_decode(&q->pucch, format, n_pucch, sf_rx, rnti, q->sf_symbols, q->ce, noise_power, bits); 
   if (ret_val < 0) {
     fprintf(stderr,"Error decoding PUCCH\n");
@@ -271,9 +270,15 @@ int srslte_enb_ul_get_pucch(srslte_enb_ul_t *q, uint16_t rnti,
       uci_data->uci_ack = pucch_bits[0];            
     }
     
-    // Decode CQI bits 
+    // PUCCH2 CQI bits are decoded inside srslte_pucch_decode() 
     if (uci_data->uci_cqi_len) {
       memcpy(uci_data->uci_cqi, pucch_bits, uci_data->uci_cqi_len*sizeof(uint8_t));
+      if (uci_data->uci_ack_len >= 1) {
+        uci_data->uci_ack = pucch_bits[20];
+      }
+      if (uci_data->uci_ack_len == 2) {
+        uci_data->uci_ack_2 = pucch_bits[21];
+      }
     }
 
     return SRSLTE_SUCCESS;

srslte/lib/phch/pucch.c

@@ -794,6 +794,8 @@ int srslte_pucch_decode(srslte_pucch_t* q, srslte_pucch_format_t format,
         bits[0] = b_max; 
         break;
       case SRSLTE_PUCCH_FORMAT_2:
+      case SRSLTE_PUCCH_FORMAT_2A:
+      case SRSLTE_PUCCH_FORMAT_2B:
         if (q->users[rnti]) {
           pucch_encode_(q, format, n_pucch, sf_idx, rnti, NULL, ref, true);
           srslte_vec_prod_conj_ccc(q->z, ref, q->z_tmp, SRSLTE_PUCCH_MAX_SYMBOLS);