Minor fixes to RA procedures

- added some text descriptions
- replaced active BWP with initial BWP in Msg3 scheduling (8.3 TS 38.213)
- fixed logging
- disabled Msg3 repetitions after first transmission (disabled RA @ MAC)

openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c

@@ -493,9 +493,13 @@ uint8_t nr_ue_get_rach(NR_PRACH_RESOURCES_t *prach_resources,
 
       if (mac->RA_window_cnt >= 0 && mac->RA_RAPID_found == 1) {
 
+        // Reset RA_active flag: it disables Msg3 retransmission (8.3 of TS 38.213)
+        // TbD Msg3 Retransmissions to be scheduled by DCI 0_0
+        mac->RA_active = 0;
         mac->RA_window_cnt = -1;
         mac->ra_state = RA_SUCCEEDED;
-        LOG_I(MAC, "[MAC][UE %d][RAPROC] Frame %d: nr_tti_tx %d: RAR successfully received \n", mod_id, frame, nr_tti_tx);
+        mac->generate_nr_prach = 2;
+        LOG_I(MAC, "[MAC][UE %d][RAPROC]: RAR successfully received \n", mod_id);
 
       } else if (mac->RA_window_cnt == 0 && !mac->RA_RAPID_found) {
 
@@ -578,7 +582,7 @@ uint8_t nr_ue_get_rach(NR_PRACH_RESOURCES_t *prach_resources,
 
         mac->RA_window_cnt--;
 
-        LOG_I(MAC, "[MAC][UE %d][RAPROC] Frame %d: nr_tti_tx %d: RAR reception not successful, (RA window count %d) \n",
+        LOG_D(MAC, "[MAC][UE %d][RAPROC][%d.%d]: RAR not received yet (RA window count %d) \n",
           mod_id,
           frame,
           nr_tti_tx,

openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

@@ -948,7 +948,7 @@ NR_UE_L2_STATE_t nr_ue_scheduler(nr_downlink_indication_t *dl_info, nr_uplink_in
 
       NR_UE_MAC_INST_t *mac = get_mac_inst(ul_info->module_id);
 
-      if (ul_info->slot_tx == mac->msg3_slot && ul_info->frame_tx == mac->msg3_frame){
+      if (mac->RA_active && ul_info->slot_tx == mac->msg3_slot && ul_info->frame_tx == mac->msg3_frame){
 
         uint8_t ulsch_input_buffer[MAX_ULSCH_PAYLOAD_BYTES];
         nr_scheduled_response_t scheduled_response;
@@ -1012,7 +1012,7 @@ NR_UE_L2_STATE_t nr_ue_scheduler(nr_downlink_indication_t *dl_info, nr_uplink_in
   return UE_CONNECTION_OK;
 }
 
-// Scheduling the Msg3 transmission according to according to TS 38.213
+// PUSCH Msg3 scheduled by RAR UL grant according to 8.3 of TS 38.213
 // Note: Msg3 tx in the uplink symbols of mixed slot
 void nr_ue_msg3_scheduler(NR_UE_MAC_INST_t *mac,
                           frame_t current_frame,
@@ -1201,8 +1201,6 @@ void nr_ue_prach_scheduler(module_id_t module_idP, frame_t frameP, sub_frame_t s
           }
         }
       }
-    } else if (mac->ra_state == RA_SUCCEEDED){
-      mac->generate_nr_prach = 2;
     }
 
     fill_scheduled_response(&scheduled_response, NULL, ul_config, NULL, module_idP, 0 /*TBR fix*/, frameP, slotP);

openair2/LAYER2/NR_MAC_UE/rar_tools_nrUE.c

@@ -103,19 +103,22 @@ void nr_config_Msg3_pdu(NR_UE_MAC_INST_t *mac,
   int ibwp_start = NRRIV2PRBOFFSET(scc->uplinkConfigCommon->initialUplinkBWP->genericParameters.locationAndBandwidth, 275);
   int ibwp_size = NRRIV2BW(scc->uplinkConfigCommon->initialUplinkBWP->genericParameters.locationAndBandwidth, 275);
 
-  //// Resource assignment from RAR
-  // Frequency domain allocation
-  if (abwp_size < 180)
-    mask = (1 << ((int) ceil(log2((abwp_size*(abwp_size+1))>>1)))) - 1;
-  else
-    mask = (1 << (28 - (int)(ceil(log2((abwp_size*(abwp_size+1))>>1))))) - 1;
-  f_alloc = Msg3_f_alloc & mask;
+  // BWP start selection according to 8.3 of TS 38.213
   pusch_config_pdu->bwp_size = ibwp_size;
   if ((ibwp_start < abwp_start) || (ibwp_size > abwp_size))
     pusch_config_pdu->bwp_start = abwp_start;
   else
     pusch_config_pdu->bwp_start = ibwp_start;
+
+  //// Resource assignment from RAR
+  // Frequency domain allocation according to 8.3 of TS 38.213
+  if (ibwp_size < 180)
+    mask = (1 << ((int) ceil(log2((ibwp_size*(ibwp_size+1))>>1)))) - 1;
+  else
+    mask = (1 << (28 - (int)(ceil(log2((ibwp_size*(ibwp_size+1))>>1))))) - 1;
+  f_alloc = Msg3_f_alloc & mask;
   nr_ue_process_dci_freq_dom_resource_assignment(pusch_config_pdu, NULL, ibwp_size, 0, f_alloc);
+
   // virtual resource block to physical resource mapping for Msg3 PUSCH (6.3.1.7 in 38.211)
   pusch_config_pdu->rb_start += ibwp_start - abwp_start;
 
@@ -250,7 +253,7 @@ uint16_t nr_ue_process_rar(module_id_t mod_id,
         LOG_D(MAC, "[UE %d][RAPROC] Got BI RAR subPDU %d\n", mod_id, ue_mac->RA_backoff_indicator);
       }
       if (rarh->RAPID == preamble_index) {
-        LOG_D(PHY, "[UE %d][RAPROC] Found RAR with the intended RAPID %d\n", mod_id, rarh->RAPID);
+        LOG_I(PHY, "[UE %d][RAPROC][%d.%d] Found RAR with the intended RAPID %d\n", mod_id, frame, slot, rarh->RAPID);
         rar = (NR_MAC_RAR *) (dlsch_buffer + n_subheaders + (n_subPDUs - 1) * sizeof(NR_MAC_RAR));
         ue_mac->RA_RAPID_found = 1;
         break;