gNB: allow more than 2 antenna ports at the Tx side

openair1/PHY/INIT/nr_parms.c

@@ -275,9 +275,9 @@ int nr_init_frame_parms(nfapi_nr_config_request_scf_t* cfg,
 
   fp->slots_per_frame = 10* fp->slots_per_subframe;
 
-  fp->nb_antenna_ports_gNB = 1; // default value until overwritten by RRCConnectionReconfiguration
-  fp->nb_antennas_rx = 1; // default value until overwritten by RRCConnectionReconfiguration
-  fp->nb_antennas_tx = 1; // default value until overwritten by RRCConnectionReconfiguration
+  fp->nb_antenna_ports_gNB = cfg->carrier_config.num_tx_ant.value;// It corresponds to pdsch_AntennaPorts
+  fp->nb_antennas_rx = cfg->carrier_config.num_rx_ant.value;      // in config_common() in config.c: HardCoded to 1
+  fp->nb_antennas_tx = 1;                                         // It corresponds to UE Tx antenna
 
   fp->symbols_per_slot = ((Ncp == NORMAL)? 14 : 12); // to redefine for different slot formats
   fp->samples_per_subframe_wCP = fp->ofdm_symbol_size * fp->symbols_per_slot * fp->slots_per_subframe;

openair2/LAYER2/NR_MAC_gNB/config.c

@@ -268,7 +268,7 @@ void config_common(int Mod_idP, int pdsch_AntennaPorts, NR_ServingCellConfigComm
     num_ssb += (cfg->ssb_table.ssb_mask_list[1].ssb_mask.value>>i)&1;
   } 
 
-  cfg->carrier_config.num_rx_ant.value = cfg->carrier_config.num_tx_ant.value;
+  cfg->carrier_config.num_rx_ant.value = 1;//HardCoded till we review the rx chain of PUSCH for num_rx_ant > 1 "cfg->carrier_config.num_tx_ant.value;"
   cfg->carrier_config.num_rx_ant.tl.tag = NFAPI_NR_CONFIG_NUM_RX_ANT_TAG;
   LOG_I(MAC,"Set TX/RX antenna number to %d (num ssb %d: %x,%x)\n",cfg->carrier_config.num_tx_ant.value,num_ssb,cfg->ssb_table.ssb_mask_list[0].ssb_mask.value,cfg->ssb_table.ssb_mask_list[1].ssb_mask.value);
   AssertFatal(cfg->carrier_config.num_tx_ant.value > 0,"carrier_config.num_tx_ant.value %d !\n",cfg->carrier_config.num_tx_ant.value );

targets/PROJECTS/GENERIC-LTE-EPC/CONF/gnb.band78.tm1.106PRB.usrpn300.conf

@@ -23,7 +23,7 @@ gNBs =
 
     ssb_SubcarrierOffset                                      = 0;
     pdsch_AntennaPorts                                        = 1;
-	
+    
     servingCellConfigCommon = (
     {
  #spCellConfigCommon
@@ -247,8 +247,15 @@ RUs = (
          max_pdschReferenceSignalPower = -27;
          max_rxgain                    = 75;
          eNB_instances  = [0];
-         #beamforming 1x4 matrix:
-         bf_weights = [0x00007fff, 0x0000, 0x0000, 0x0000];
+         ##beamforming 1x2 matrix: 1 layer x 2 antennas
+         bf_weights = [0x00007fff, 0x0000];
+         ##beamforming 1x4 matrix: 1 layer x 4 antennas
+         #bf_weights = [0x00007fff, 0x0000,0x0000, 0x0000];
+         ## beamforming 2x2 matrix:
+         # bf_weights = [0x00007fff, 0x00000000, 0x00000000, 0x00007fff];
+         ## beamforming 4x4 matrix:
+         #bf_weights = [0x00007fff, 0x0000, 0x0000, 0x0000, 0x00000000, 0x00007fff, 0x0000, 0x0000, 0x0000, 0x0000, 0x00007fff, 0x0000, 0x0000, 0x0000, 0x0000, 0x00007fff];
+
          sdr_addrs = "addr=192.168.10.2,mgmt_addr=192.168.10.2,second_addr=192.168.20.2";
          clock_src = "external";
     }