Added periodic RI on PUCCH for TM3 and TM4

lib/examples/pdsch_ue.c

@@ -518,7 +518,7 @@ int main(int argc, char **argv) {
     
   // Variables for measurements 
   uint32_t nframes=0;
-  uint32_t ri = 0, pmi = 0;
+  uint8_t ri = 0, pmi = 0;
   float rsrp0=0.0, rsrp1=0.0, rsrq=0.0, noise=0.0, enodebrate = 0.0, uerate = 0.0,
       sinr[SRSLTE_MAX_LAYERS][SRSLTE_MAX_CODEBOOKS], cn = 0.0;
   bool decode_pdsch = false; 

lib/include/srslte/phy/phch/cqi.h

@@ -41,11 +41,14 @@
 #include "srslte/phy/common/phy_common.h"
 
 #define SRSLTE_CQI_MAX_BITS 64
+#define SRSLTE_DIF_CQI_MAX_BITS 3
+#define SRSLTE_PMI_MAX_BITS 4
 
 typedef struct {
   bool     configured; 
   uint32_t pmi_idx; 
   uint32_t ri_idx;
+  bool ri_idx_present;
   bool     simul_cqi_ack;
   bool     format_is_subband; 
   uint32_t subband_size; 

lib/include/srslte/phy/phch/uci.h

@@ -64,6 +64,10 @@ typedef struct SRSLTE_API {
 typedef struct SRSLTE_API {
   uint8_t  uci_cqi[SRSLTE_CQI_MAX_BITS];
   uint32_t uci_cqi_len;
+  uint8_t  uci_dif_cqi[SRSLTE_DIF_CQI_MAX_BITS];
+  uint32_t uci_dif_cqi_len;
+  uint8_t  uci_pmi[SRSLTE_PMI_MAX_BITS];
+  uint8_t  uci_pmi_len;
   uint8_t  uci_ri;  // Only 1-bit supported for RI
   uint32_t uci_ri_len;
   uint8_t  uci_ack;   // 1st codeword bit for HARQ-ACK

lib/include/srslte/phy/ue/ue_dl.h

@@ -182,8 +182,8 @@ SRSLTE_API int srslte_ue_dl_decode_rnti(srslte_ue_dl_t *q,
                                         bool acks[SRSLTE_MAX_CODEWORDS]);
 
 SRSLTE_API int srslte_ue_dl_ri_pmi_select(srslte_ue_dl_t *q,
-                                          uint32_t *ri,
+                                          uint8_t *ri,
-                                          uint32_t *pmi,
+                                          uint8_t *pmi,
                                           float *current_sinr);
 
 SRSLTE_API int srslte_ue_dl_ri_select(srslte_ue_dl_t *q,

lib/src/phy/ue/ue_dl.c

@@ -454,10 +454,10 @@ int srslte_ue_dl_decode_rnti(srslte_ue_dl_t *q, cf_t *input[SRSLTE_MAX_PORTS],
 
 /* Compute the Rank Indicator (RI) and Precoder Matrix Indicator (PMI) by computing the Signal to Interference plus
  * Noise Ratio (SINR), valid for TM4 */
-int srslte_ue_dl_ri_pmi_select(srslte_ue_dl_t *q, uint32_t *ri, uint32_t *pmi, float *current_sinr) {
+int srslte_ue_dl_ri_pmi_select(srslte_ue_dl_t *q, uint8_t *ri, uint8_t *pmi, float *current_sinr) {
   float noise_estimate = srslte_chest_dl_get_noise_estimate(&q->chest);
   float best_sinr = -INFINITY;
-  uint32_t best_pmi = 0, best_ri = 0;
+  uint8_t best_pmi = 0, best_ri = 0;
 
   if (q->cell.nof_ports < 2 || q->nof_rx_antennas < 2) {
     /* Do nothing */
@@ -471,11 +471,11 @@ int srslte_ue_dl_ri_pmi_select(srslte_ue_dl_t *q, uint32_t *ri, uint32_t *pmi, f
 
     /* Select the best Rank indicator (RI) and Precoding Matrix Indicator (PMI) */
     for (uint32_t nof_layers = 1; nof_layers <= 2; nof_layers++) {
-      float _sinr = q->sinr[nof_layers - 1][q->pmi[nof_layers - 1]] * nof_layers;
+      float _sinr = q->sinr[nof_layers - 1][q->pmi[nof_layers - 1]] * nof_layers * nof_layers;
       if (_sinr > best_sinr + 0.1) {
         best_sinr = _sinr;
-        best_pmi = q->pmi[nof_layers - 1];
+        best_pmi = (uint8_t) q->pmi[nof_layers - 1];
-        best_ri = nof_layers;
+        best_ri = (uint8_t) (nof_layers - 1);
       }
     }
 

lib/src/phy/ue/ue_ul.c

@@ -230,6 +230,14 @@ void pucch_encode_bits(srslte_uci_data_t *uci_data, srslte_pucch_format_t format
     pucch_bits[1] = uci_data->uci_ack_2; // this will be ignored in format 1a 
   }
   if (format >= SRSLTE_PUCCH_FORMAT_2) {
+    /* Append Differential CQI */
+    memcpy(&uci_data->uci_cqi[uci_data->uci_cqi_len], uci_data->uci_dif_cqi, uci_data->uci_dif_cqi_len);
+    uci_data->uci_cqi_len += uci_data->uci_dif_cqi_len;
+
+    /* Append PMI */
+    memcpy(&uci_data->uci_cqi[uci_data->uci_cqi_len], uci_data->uci_pmi, uci_data->uci_pmi_len);
+    uci_data->uci_cqi_len += uci_data->uci_pmi_len;
+
     srslte_uci_encode_cqi_pucch(uci_data->uci_cqi, uci_data->uci_cqi_len, pucch_bits);
     if (format > SRSLTE_PUCCH_FORMAT_2) {
       pucch2_bits[0] = uci_data->uci_ack; 

srsue/src/phy/phch_worker.cc

@@ -230,11 +230,23 @@ void phch_worker::work_imp()
       }
 
       /* Select Rank Indicator by computing Condition Number */
-      if (phy->config->dedicated.antenna_info_explicit_value.tx_mode == LIBLTE_RRC_TRANSMISSION_MODE_3 ||
+      if (phy->config->dedicated.antenna_info_explicit_value.tx_mode == LIBLTE_RRC_TRANSMISSION_MODE_3) {
-          phy->config->dedicated.antenna_info_explicit_value.tx_mode == LIBLTE_RRC_TRANSMISSION_MODE_4) {
         float cn = 0.0f;
         srslte_ue_dl_ri_select(&ue_dl, &uci_data.uci_ri, &cn);
         uci_data.uci_ri_len = 1;
+      } else if (phy->config->dedicated.antenna_info_explicit_value.tx_mode == LIBLTE_RRC_TRANSMISSION_MODE_4){
+        float sinr = 0.0f;
+        uint8 packed_pmi = 0;
+        srslte_ue_dl_ri_pmi_select(&ue_dl, &uci_data.uci_ri, &packed_pmi, &sinr);
+        srslte_bit_unpack_vector(&packed_pmi, uci_data.uci_pmi, 2);
+        uci_data.uci_ri_len = 1;
+        if (uci_data.uci_ri == 0) {
+          uci_data.uci_pmi_len = 2;
+          uci_data.uci_dif_cqi_len = 0;
+        } else {
+          uci_data.uci_pmi_len = 1;
+          uci_data.uci_dif_cqi_len = 3;
+        }
       }
     }
   }
@@ -714,7 +726,16 @@ void phch_worker::set_uci_periodic_cqi()
   int cqi_max       = phy->args->cqi_max;
   
   if (period_cqi.configured && rnti_is_set) {
-    if (srslte_cqi_send(period_cqi.pmi_idx, (tti+4)%10240)) {
+    if (period_cqi.ri_idx_present && srslte_ri_send(period_cqi.pmi_idx, period_cqi.ri_idx, (tti+4)%10240)) {
+      if (uci_data.uci_ri_len) {
+        uci_data.uci_cqi[0] = uci_data.uci_ri;
+        uci_data.uci_cqi_len = uci_data.uci_ri_len;
+        uci_data.uci_ri_len = 0;
+        uci_data.uci_dif_cqi_len = 0;
+        uci_data.uci_pmi_len = 0;
+        Info("PUCCH: Periodic RI=%d\n", uci_data.uci_cqi[0]);
+      }
+    } else if (srslte_cqi_send(period_cqi.pmi_idx, (tti+4)%10240)) {
       srslte_cqi_value_t cqi_report;
       if (period_cqi.format_is_subband) {
         // TODO: Implement subband periodic reports
@@ -876,11 +897,12 @@ void phch_worker::encode_pucch()
   float tx_power = srslte_ue_ul_pucch_power(&ue_ul, phy->pathloss, ue_ul.last_pucch_format, uci_data.uci_cqi_len, uci_data.uci_ack_len);
   float gain = set_power(tx_power);  
   
-  Info("PUCCH: power=%.2f dBm, tti_tx=%d, n_cce=%3d, n_pucch=%d, n_prb=%d, ack=%s%s, sr=%s, cfo=%.1f Hz%s\n",
+  Info("PUCCH: power=%.2f dBm, tti_tx=%d, n_cce=%3d, n_pucch=%d, n_prb=%d, ack=%s%s, ri=%s, sr=%s, cfo=%.1f Hz%s\n",
          tx_power, (tti+4)%10240, 
          last_dl_pdcch_ncce, ue_ul.pucch.last_n_pucch, ue_ul.pucch.last_n_prb, 
        uci_data.uci_ack_len>0?(uci_data.uci_ack?"1":"0"):"no",
        uci_data.uci_ack_len>1?(uci_data.uci_ack_2?"1":"0"):"",
+       uci_data.uci_ri_len>0?(uci_data.uci_ri?"1":"0"):"no",
        uci_data.scheduling_request?"yes":"no",
          cfo*15000, timestr);        
   }   
@@ -1017,6 +1039,13 @@ void phch_worker::set_ul_params(bool pregen_disabled)
                                  LIBLTE_RRC_CQI_FORMAT_INDICATOR_PERIODIC_SUBBAND_CQI;
   period_cqi.subband_size      = dedicated->cqi_report_cnfg.report_periodic.format_ind_periodic_subband_k;
 
+  if (dedicated->cqi_report_cnfg.report_periodic.ri_cnfg_idx_present) {
+    period_cqi.ri_idx = dedicated->cqi_report_cnfg.report_periodic.ri_cnfg_idx;
+    period_cqi.ri_idx_present = true;
+  } else {
+    period_cqi.ri_idx_present = false;
+  }
+
   /* SR configuration */
   I_sr                         = dedicated->sched_request_cnfg.sr_cnfg_idx;