Adding first layer timing advance

- Added new structure to hold timing advance parameters
   - Made SIB19 related calculation to save to this struct
   - Modified in ra to get ta struct values

executables/nr-ue.c

@@ -156,7 +156,7 @@ void init_nr_ue_vars(PHY_VARS_NR_UE *ue, uint8_t UE_id)
   ue->if_inst     = nr_ue_if_module_init(UE_id);
   ue->dci_thres   = 0;
   ue->target_Nid_cell = -1;
-  ue->timing_advance = ue->frame_parms.samples_per_subframe * get_nrUE_params()->ntn_ta_common;
+  ue->timing_advance = ue->frame_parms.samples_per_subframe * 2 * get_nrUE_params()->ntn_ta_common;
 
   check_position(UE_id);
   // initialize all signal buffers

openair2/LAYER2/NR_MAC_UE/config_ue.c

@@ -1775,16 +1775,23 @@ void nr_rrc_mac_config_req_sib19_r17(module_id_t module_id, NR_SIB19_r17_t *sib1
   // ntn-Config-r17 deep copy into mac
   asn_copy(&asn_DEF_NR_NTN_Config_r17, (void **)&mac->sc_info.ntn_Config_r17, sib19_r17->ntn_Config_r17);
 
+  // populate ntn_ta structure from mac
   // if ephemerisInfo_r17 present in SIB19
   if (mac->sc_info.ntn_Config_r17->ephemerisInfo_r17 && mac->sc_info.ntn_Config_r17->ephemerisInfo_r17->choice.positionVelocity_r17
       && (mac->sc_info.ntn_Config_r17->ephemerisInfo_r17->choice.positionVelocity_r17->positionX_r17 != 0
           || mac->sc_info.ntn_Config_r17->ephemerisInfo_r17->choice.positionVelocity_r17->positionY_r17 != 0
           || mac->sc_info.ntn_Config_r17->ephemerisInfo_r17->choice.positionVelocity_r17->positionZ_r17 != 0)) {
-    get_nrUE_params()->ntn_ta_common =
+    mac->ntn_ta.N_UE_TA_adj =
         calculate_ue_sat_ta(get_position(module_id), mac->sc_info.ntn_Config_r17->ephemerisInfo_r17->choice.positionVelocity_r17);
   }
-
-  get_nrUE_params()->ntn_koffset = *mac->sc_info.ntn_Config_r17->cellSpecificKoffset_r17;
+  // if cellSpecificKoffset_r17 is present
+  if (sib19_r17->ntn_Config_r17->cellSpecificKoffset_r17) {
+    mac->ntn_ta.cell_specific_k_offset = *sib19_r17->ntn_Config_r17->cellSpecificKoffset_r17;
+  }
+  // Check if ta_Info_r17 is present and convert directly ta_Common_r17 (is in units of 4.072e-3 µs)
+  if (sib19_r17->ntn_Config_r17->ta_Info_r17) {
+    mac->ntn_ta.N_common_ta_adj = sib19_r17->ntn_Config_r17->ta_Info_r17->ta_Common_r17 * 4.072e-6;
+  }
 }
 
 static void handle_reconfiguration_with_sync(NR_UE_MAC_INST_t *mac,

openair2/LAYER2/NR_MAC_UE/mac_defs.h

@@ -554,6 +554,13 @@ typedef struct {
   A_SEQUENCE_OF(si_schedinfo_config_t) si_SchedInfo_list;
 } si_schedInfo_t;
 
+typedef struct ntn_timing_advance_components {
+// N_common_ta_adj and N_UE_TA_adj are in ms
+double N_common_ta_adj;
+double N_UE_TA_adj;
+long cell_specific_k_offset;
+} ntn_timing_advance_componets_t;
+
 /*!\brief Top level UE MAC structure */
 typedef struct NR_UE_MAC_INST_s {
   module_id_t ue_id;
@@ -623,6 +630,8 @@ typedef struct NR_UE_MAC_INST_s {
   int p_Max_alt;
   int n_ta_offset; // -1 not present, otherwise value to be applied
 
+  ntn_timing_advance_componets_t ntn_ta;
+
   long pdsch_HARQ_ACK_Codebook;
 
   NR_Type0_PDCCH_CSS_config_t type0_PDCCH_CSS_config;

openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c

@@ -40,16 +40,13 @@
 
 #include <executables/softmodem-common.h>
 #include "openair2/LAYER2/RLC/rlc.h"
+#include "openair2/LAYER2/NR_MAC_UE/mac_defs.h"
 
 #include "nr-uesoftmodem.h"
 
-static double get_ta_Common_ms(NR_NTN_Config_r17_t *ntn_Config_r17)
+static double get_ta_Common_ms(const ntn_timing_advance_componets_t* ntn_ta)
 {
-  if (ntn_Config_r17 && ntn_Config_r17->ta_Info_r17) {
-    // ta_Common_r17 is in units of 4.072e-3 µs
-    return (ntn_Config_r17->ta_Info_r17->ta_Common_r17 * 4.072e-6 + get_nrUE_params()->ntn_ta_common) * 2;
-  }
-  return 0.0;
+  return (ntn_ta->N_common_ta_adj + ntn_ta->N_UE_TA_adj) * 2;
 }
 
 int16_t get_prach_tx_power(NR_UE_MAC_INST_t *mac)
@@ -625,7 +622,7 @@ void nr_Msg3_transmitted(NR_UE_MAC_INST_t *mac, uint8_t CC_id, frame_t frameP, s
 {
   RA_config_t *ra = &mac->ra;
   NR_RACH_ConfigCommon_t *nr_rach_ConfigCommon = mac->current_UL_BWP->rach_ConfigCommon;
-  const double ta_Common_ms = get_ta_Common_ms(mac->sc_info.ntn_Config_r17);
+  const double ta_Common_ms = get_ta_Common_ms(&mac->ntn_ta);
   const int mu = mac->current_UL_BWP->scs;
   const int slots_per_ms = nr_slots_per_frame[mu] / 10;