added no_DTX function to eNB. This fills the TX subframes which have no PDSCH with a fake pdsch. It avoids switching between TX/RX in TDD systems during the DL periods.

openair1/PHY/INIT/lte_init.c

@@ -347,6 +347,31 @@ void phy_config_sib13_eNB(module_id_t Mod_id,int CC_id,int mbsfn_Area_idx,
   lte_gold_mbsfn_khz_1dot25 (fp, RC.eNB[Mod_id][CC_id]->lte_gold_mbsfn_khz_1dot25_table, fp->Nid_cell_mbsfn);
 }
 
+void fill_subframe_mask(PHY_VARS_eNB *eNB) {
+
+  AssertFatal(eNB->subframe_mask!=NULL,"Subframe mask is null\n");
+  int32_t **dummy_tx=eNB->common_vars.txdataF;
+  eNB->common_vars.txdataF = eNB->subframe_mask;
+  
+  for (int sf=0;sf<10;sf++) {
+    if (subframe_select(&eNB->frame_parms,sf)==SF_DL) {
+      LTE_DL_eNB_HARQ_t *dlsch_harq=eNB->dlsch[0][0]->harq_processes[0];
+      L1_rxtx_proc_t proc;
+      proc.frame_tx=0;
+      proc.subframe_tx=sf;
+      eNB->dlsch[0][0]->harq_ids[0][sf]=0;
+      eNB->dlsch[0][0]->rnti=0x1234;
+      dlsch_harq->nb_rb=12;
+      dlsch_harq->rb_alloc[0]=0xfff;
+      dlsch_harq->Qm=2;
+      dlsch_harq->Nl=1;
+      dlsch_harq->pdsch_start=1;
+      dlsch_harq->mimo_mode=(eNB->frame_parms.nb_antenna_ports_eNB>1) ? ALAMOUTI : SISO;
+      pdsch_procedures(eNB,&proc,0,eNB->dlsch[0][0]);
+    }
+  }
+  eNB->common_vars.txdataF = dummy_tx;
+}
 
 int phy_init_lte_eNB(PHY_VARS_eNB *eNB,
                      unsigned char is_secondary_eNB,
@@ -400,6 +425,9 @@ int phy_init_lte_eNB(PHY_VARS_eNB *eNB,
   if (NFAPI_MODE!=NFAPI_MODE_VNF) {
     common_vars->rxdata  = (int32_t **)NULL;
     common_vars->txdataF = (int32_t **)malloc16(NB_ANTENNA_PORTS_ENB*sizeof(int32_t *));
+    if (eNB->use_DTX==0) {
+      eNB->subframe_mask = (int32_t **)malloc16(NB_ANTENNA_PORTS_ENB*sizeof(int32_t *));
+    }
     common_vars->rxdataF = (int32_t **)malloc16(64*sizeof(int32_t *));
     LOG_I(PHY,"[INIT] NB_ANTENNA_PORTS_ENB:%d fp->nb_antenna_ports_eNB:%d\n", NB_ANTENNA_PORTS_ENB, fp->nb_antenna_ports_eNB);
 
@@ -409,6 +437,7 @@ int phy_init_lte_eNB(PHY_VARS_eNB *eNB,
         LOG_I(PHY,"[INIT] common_vars->txdataF[%d] = %p (%lu bytes)\n",
               i,common_vars->txdataF[i],
               fp->ofdm_symbol_size*fp->symbols_per_tti*10*sizeof(int32_t));
+	if (i<fp->nb_antenna_ports_eNB) eNB->subframe_mask[i] = malloc16_clear(fp->ofdm_symbol_size*fp->symbols_per_tti*10*sizeof(int32_t) );
       }
     }
 

openair1/PHY/defs_eNB.h

@@ -517,6 +517,9 @@ typedef struct PHY_VARS_eNB_s {
   uint8_t pbch_pdu[4]; //PBCH_PDU_SIZE
   char eNB_generate_rar;
 
+  /// indicator that eNB signal generation uses DTX (i.e. signal is cleared in each subframe
+  int use_DTX;
+  int32_t **subframe_mask;
   /// Indicator set to 0 after first SR
   uint8_t first_sr[NUMBER_OF_UE_MAX];
 

openair1/SCHED/phy_procedures_lte_eNb.c

@@ -521,7 +521,11 @@ void phy_procedures_eNB_TX(PHY_VARS_eNB *eNB,
 
   // clear the transmit data array for the current subframe
   for (aa = 0; aa < fp->nb_antenna_ports_eNB; aa++) {
-    memset (&eNB->common_vars.txdataF[aa][subframe * fp->ofdm_symbol_size * (fp->symbols_per_tti)], 0, fp->ofdm_symbol_size * (fp->symbols_per_tti) * sizeof (int32_t));
+    if (eNB->use_DTX==0) 
+      memcpy(&eNB->common_vars.txdataF[aa][subframe * fp->ofdm_symbol_size * (fp->symbols_per_tti)],
+	     &eNB->subframe_mask[aa][subframe*fp->ofdm_symbol_size*fp->symbols_per_tti],
+	     fp->ofdm_symbol_size * (fp->symbols_per_tti) * sizeof (int32_t));
+    else memset(&eNB->common_vars.txdataF[aa][subframe * fp->ofdm_symbol_size * (fp->symbols_per_tti)], 0, fp->ofdm_symbol_size * (fp->symbols_per_tti) * sizeof (int32_t));
   }
 
   if (NFAPI_MODE==NFAPI_MONOLITHIC || NFAPI_MODE==NFAPI_MODE_PNF) {

targets/RT/USER/lte-enb.c

@@ -1134,6 +1134,8 @@ void init_transport(PHY_VARS_eNB *eNB) {
   eNB->FULL_MUMIMO_transmissions = 0;
   eNB->check_for_SUMIMO_transmissions = 0;
   fp->pucch_config_common.deltaPUCCH_Shift = 1;
+  if (eNB->use_DTX == 0) fill_subframe_mask(eNB);
+  
 }