Review Msg3 tranmission

- now transmitting resetting Msg3 slot and frame to -1 after transmission
- cleanup in Msg3 scheduling
- checked Msg3 pdu configuration against the 3GPP specs

openair2/LAYER2/NR_MAC_UE/mac_defs.h

@@ -285,9 +285,9 @@ typedef struct {
   int starting_preamble_nb;
 
   /// Scheduled TX frame for RA Msg3
-  frame_t msg3_frame;
+  int msg3_frame;
   /// Scheduled TX slot for RA Msg3
-  slot_t msg3_slot;
+  int msg3_slot;
   /// Received TPC command (in dB) from RAR
   int8_t Msg3_TPC;
   /// Flag to indicate whether it is the first Msg3 to be transmitted

openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c

@@ -482,6 +482,7 @@ void nr_Msg3_transmitted(module_id_t mod_id, uint8_t CC_id, frame_t frameP, uint
 // - fix rrc data req logic
 // - retrieve TBS
 // - add mac_rrc_nr_data_req_ue, etc ...
+// - Msg3 Retransmissions to be scheduled by DCI 0_0
 uint8_t nr_ue_get_rach(NR_PRACH_RESOURCES_t *prach_resources,
                        fapi_nr_ul_config_prach_pdu *prach_pdu,
                        module_id_t mod_id,
@@ -591,7 +592,6 @@ uint8_t nr_ue_get_rach(NR_PRACH_RESOURCES_t *prach_resources,
 
       if (ra->RA_window_cnt >= 0 && ra->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
 
         nr_ra_succeeded(mod_id, frame, nr_slot_tx);
 

openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

@@ -1277,9 +1277,7 @@ 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(mod_id);
     RA_config_t *ra = &mac->ra;
 
-    if (ra->ra_state == WAIT_RAR){
-
-      if (ra->RA_active && ul_info->slot_tx == ra->msg3_slot && ul_info->frame_tx == ra->msg3_frame){
+    if (ul_info->slot_tx == ra->msg3_slot && ul_info->frame_tx == ra->msg3_frame){
 
       uint8_t ulsch_input_buffer[MAX_ULSCH_PAYLOAD_BYTES];
       nr_scheduled_response_t scheduled_response;
@@ -1341,8 +1339,13 @@ NR_UE_L2_STATE_t nr_ue_scheduler(nr_downlink_indication_t *dl_info, nr_uplink_in
         nr_Msg3_transmitted(ul_info->module_id, ul_info->cc_id, ul_info->frame_tx, ul_info->gNB_index);
       }
 
+      // disable future transmissions of Msg3 at the next (frame, slot) occasion
+      ra->msg3_slot = -1;
+      ra->msg3_frame = -1;
+
     }
-    } else if (ra->ra_state == RA_SUCCEEDED || get_softmodem_params()->phy_test) {
+
+    if (ra->ra_state == RA_SUCCEEDED || get_softmodem_params()->phy_test) {
 
       uint8_t nb_dmrs_re_per_rb;
       uint8_t ulsch_input_buffer[MAX_ULSCH_PAYLOAD_BYTES];

openair2/LAYER2/NR_MAC_UE/rar_tools_nrUE.c

@@ -52,6 +52,14 @@
 // #define DEBUG_RAR
 // #define DEBUG_MSG3
 
+// Configuration of Msg3 PDU according to clauses:
+// - 8.3 of 3GPP TS 38.213 version 16.3.0 Release 16
+// - 6.1.2.2 of TS 38.214
+// - 6.1.3 of TS 38.214
+// - 6.2.2 of TS 38.214
+// - 6.1.4.2 of TS 38.214
+// - 6.4.1.1.1 of TS 38.211
+// - 6.3.1.7 of 38.211
 void nr_config_Msg3_pdu(NR_UE_MAC_INST_t *mac,
                         int Msg3_f_alloc,
                         uint8_t Msg3_t_alloc,
@@ -75,11 +83,8 @@ void nr_config_Msg3_pdu(NR_UE_MAC_INST_t *mac,
   printf("[DEBUG_MSG3] Configuring 1 Msg3 PDU of %d UL pdus \n", ul_config->number_pdus);
   #endif
 
-  // Num PRB Overhead from PUSCH-ServingCellConfig
-  if (mac->scg->spCellConfig->spCellConfigDedicated->uplinkConfig->pusch_ServingCellConfig->choice.setup->xOverhead == NULL)
+  // For Msg3 or MsgA PUSCH transmission the N_PRB_oh is always set to 0
   N_PRB_oh = 0;
-  else
-    N_PRB_oh = *mac->scg->spCellConfig->spCellConfigDedicated->uplinkConfig->pusch_ServingCellConfig->choice.setup->xOverhead;
 
   // active BWP start
   int abwp_start = NRRIV2PRBOFFSET(ubwp->bwp_Common->genericParameters.locationAndBandwidth, MAX_BWP_SIZE);
@@ -129,7 +134,11 @@ void nr_config_Msg3_pdu(NR_UE_MAC_INST_t *mac,
   // Frequency hopping
   pusch_config_pdu->frequency_hopping = freq_hopping;
   // TC-RNTI
+  if (ra->t_crnti) {
     pusch_config_pdu->rnti = ra->t_crnti;
+  } else {
+    pusch_config_pdu->rnti = mac->crnti;
+  }
 
   // DM-RS configuration according to 6.2.2 UE DM-RS transmission procedure in 38.214
   pusch_config_pdu->dmrs_config_type = pusch_dmrs_type1;