ssb slot computation from starting symbol in sib1 function

openair2/LAYER2/NR_MAC_COMMON/nr_mac_common.c

@@ -35,6 +35,13 @@
 
 #define reserved 0xffff
 
+// start symbols for SSB types A,B,C,D,E
+uint16_t symbol_ssb_AC[8]={2,8,16,22,30,36,44,50};
+uint16_t symbol_ssb_BD[64]={4,8,16,20,32,36,44,48,60,64,72,76,88,92,100,104,144,148,156,160,172,176,184,188,200,204,212,216,228,232,240,244,284,288,
+                            296,300,312,316,324,328,340,344,352,356,368,372,380,384,424,428,436,440,452,456,464,468,480,484,492,496,508,512,520,524};
+uint16_t symbol_ssb_E[64]={8,12,16,20,32,36,40,44,64,68,72,76,88,92,96,100,120,124,128,132,144,148,152,156,176,180,184,188,200,204,208,212,288,292,
+                           296,300,312,316,320,324,344,348,352,356,368,372,376,380,400,404,408,412,424,428,432,436,456,460,464,468,480,484,488,492};
+
 const uint8_t nr_slots_per_frame[5] = {10, 20, 40, 80, 160};
 
 // Table 6.3.3.1-5 (38.211) NCS for preamble formats with delta_f_RA = 1.25 KHz
@@ -3109,12 +3116,23 @@ void get_band(uint64_t downlink_frequency,
 	    "Can't find EUTRA band for frequency %lu\n", downlink_frequency);
 }
 
+uint16_t get_ssb_start_symbol(const long band, NR_SubcarrierSpacing_t scs, int i_ssb) {
 
-uint32_t get_ssb_slot(uint32_t ssb_index){
-  //  this function now only support f <= 3GHz
-  return ssb_index & 0x3 ;
-
-  //  return first_symbol(case, freq, ssb_index) / 14
+  switch (scs) {
+    case NR_SubcarrierSpacing_kHz15:
+      return symbol_ssb_AC[i_ssb];  //type A
+    case NR_SubcarrierSpacing_kHz30:
+      if (band == 5 || band == 66)
+        return symbol_ssb_BD[i_ssb];  //type B
+      else
+        return symbol_ssb_AC[i_ssb];  //type C
+    case NR_SubcarrierSpacing_kHz120:
+      return symbol_ssb_BD[i_ssb];  //type D
+    case NR_SubcarrierSpacing_kHz240:
+      return symbol_ssb_E[i_ssb];
+    default:
+      AssertFatal(1 == 0, "SCS %ld not allowed for SSB \n",scs);
+  }
 }
 
 void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PDCCH_CSS_config,
@@ -3122,6 +3140,7 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
                                            NR_MIB_t *mib,
                                            uint8_t num_slot_per_frame,
                                            uint8_t ssb_subcarrier_offset,
+                                           uint16_t ssb_start_symbol,
                                            NR_SubcarrierSpacing_t scs_ssb,
                                            frequency_range_t frequency_range,
                                            uint32_t ssb_index,
@@ -3148,6 +3167,8 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
   type0_PDCCH_CSS_config->ssb_index = ssb_index;
   type0_PDCCH_CSS_config->frame = frameP;
 
+  uint8_t ssb_slot = ssb_start_symbol/14;
+
   uint32_t is_condition_A = (ssb_subcarrier_offset == 0);   //  38.213 ch.13
   uint32_t index_4msb = (mib->pdcch_ConfigSIB1.controlResourceSetZero);
   uint32_t index_4lsb = (mib->pdcch_ConfigSIB1.searchSpaceZero);
@@ -3361,7 +3382,7 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
       AssertFatal(index_4lsb == 0, "38.213 Table 13-13 4 LSB out of range\n");
       //  PDCCH monitoring occasions (SFN and slot number) same as SSB frame-slot
       //                sfn_c = SFN_C_EQ_SFN_SSB;
-      type0_PDCCH_CSS_config->n_c = get_ssb_slot(type0_PDCCH_CSS_config->ssb_index);
+      type0_PDCCH_CSS_config->n_c = ssb_slot;
       switch(type0_PDCCH_CSS_config->ssb_index & 0x3){    //  ssb_index(i) mod 4
         case 0:
           type0_PDCCH_CSS_config->first_symbol_index = 0;
@@ -3383,7 +3404,7 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
       AssertFatal(index_4lsb == 0, "38.213 Table 13-14 4 LSB out of range\n");
       //  PDCCH monitoring occasions (SFN and slot number) same as SSB frame-slot
       //                sfn_c = SFN_C_EQ_SFN_SSB;
-      type0_PDCCH_CSS_config->n_c = get_ssb_slot(type0_PDCCH_CSS_config->ssb_index);
+      type0_PDCCH_CSS_config->n_c = ssb_slot;
       switch(type0_PDCCH_CSS_config->ssb_index & 0x7){    //  ssb_index(i) mod 8
         case 0:
           type0_PDCCH_CSS_config->first_symbol_index = 0;
@@ -3399,11 +3420,11 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
           break;
         case 4:
           type0_PDCCH_CSS_config->first_symbol_index = 12;
-          type0_PDCCH_CSS_config->n_c = get_ssb_slot(type0_PDCCH_CSS_config->ssb_index) - 1;
+          type0_PDCCH_CSS_config->n_c = ssb_slot - 1;
           break;
         case 5:
           type0_PDCCH_CSS_config->first_symbol_index = 13;
-          type0_PDCCH_CSS_config->n_c = get_ssb_slot(type0_PDCCH_CSS_config->ssb_index) - 1;
+          type0_PDCCH_CSS_config->n_c = ssb_slot - 1;
           break;
         case 6:
           type0_PDCCH_CSS_config->first_symbol_index = 0;
@@ -3425,7 +3446,7 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
       AssertFatal(index_4lsb == 0, "38.213 Table 13-15 4 LSB out of range\n");
       //  PDCCH monitoring occasions (SFN and slot number) same as SSB frame-slot
       //                sfn_c = SFN_C_EQ_SFN_SSB;
-      type0_PDCCH_CSS_config->n_c = get_ssb_slot(type0_PDCCH_CSS_config->ssb_index);
+      type0_PDCCH_CSS_config->n_c = ssb_slot;
       switch(type0_PDCCH_CSS_config->ssb_index & 0x3){    //  ssb_index(i) mod 4
         case 0:
           type0_PDCCH_CSS_config->first_symbol_index = 4;

openair2/LAYER2/NR_MAC_COMMON/nr_mac_common.h

@@ -131,11 +131,14 @@ void get_type0_PDCCH_CSS_config_parameters(NR_Type0_PDCCH_CSS_config_t *type0_PD
                                            NR_MIB_t *mib,
                                            uint8_t num_slot_per_frame,
                                            uint8_t ssb_subcarrier_offset,
+                                           uint16_t ssb_start_symbol,
                                            NR_SubcarrierSpacing_t scs_ssb,
                                            frequency_range_t frequency_range,
                                            uint32_t ssb_index,
                                            uint32_t ssb_offset_point_a);
 
+uint16_t get_ssb_start_symbol(const long band, NR_SubcarrierSpacing_t scs, int i_ssb);
+
 int16_t get_N_RA_RB (int delta_f_RA_PRACH,int delta_f_PUSCH);
 
 bool set_dl_ptrs_values(NR_PTRS_DownlinkConfig_t *ptrs_config,

openair2/LAYER2/NR_MAC_UE/mac_defs.h

@@ -318,7 +318,7 @@ typedef struct {
   NR_TAG_Config_t                 *tag_Config;
   NR_PHR_Config_t                 *phr_Config;
   NR_RNTI_Value_t                 *cs_RNTI;
-  NR_MIB_t                         *mib;
+  NR_MIB_t                        *mib;
 
   NR_BWP_Downlink_t               *DLbwp[MAX_NUM_BWP];
   NR_BWP_Uplink_t                 *ULbwp[MAX_NUM_BWP];

openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

@@ -104,6 +104,7 @@ int8_t nr_ue_decode_mib(module_id_t module_id,
   LOG_I(MAC,"[L2][MAC] decode mib\n");
 
   NR_UE_MAC_INST_t *mac = get_mac_inst(module_id);
+  NR_ServingCellConfigCommon_t    *scc = mac->scc;
   frequency_range_t frequency_range;
   nr_mac_rrc_data_ind_ue( module_id, cc_id, gNB_index, NR_BCCH_BCH, (uint8_t *) pduP, 3 );    //  fixed 3 bytes MIB PDU
     
@@ -143,22 +144,37 @@ int8_t nr_ue_decode_mib(module_id_t module_id,
   //storing ssb index in the mac structure
   mac->mib_ssb = ssb_index;
 
-  // TODO fix this (it shouldn't be taken from config)
-  uint8_t scs_ssb = mac->phy_config.config_req.ssb_config.scs_common;
-
-  get_type0_PDCCH_CSS_config_parameters(&mac->type0_PDCCH_CSS_config,
-                                        frame,
-                                        mac->mib,
-                                        nr_slots_per_frame[scs_ssb],
-                                        ssb_subcarrier_offset,
-                                        scs_ssb,
-                                        frequency_range,
-                                        ssb_index,
-                                        mac->phy_config.config_req.ssb_table.ssb_offset_point_a);
-
-  mac->type0_pdcch_ss_mux_pattern = mac->type0_PDCCH_CSS_config.type0_pdcch_ss_mux_pattern;
-  mac->type0_pdcch_ss_sfn_c = mac->type0_PDCCH_CSS_config.sfn_c;
-  mac->type0_pdcch_ss_n_c = mac->type0_PDCCH_CSS_config.n_c;
+  if (get_softmodem_params()->sa == 1) {
+
+    // TODO these values shouldn't be taken from SCC in SA
+    uint8_t scs_ssb = *scc->ssbSubcarrierSpacing;
+    uint32_t band = *scc->downlinkConfigCommon->frequencyInfoDL->frequencyBandList.list.array[0];
+    int scs_scaling = 1<<scs_ssb;
+    if (scc->downlinkConfigCommon->frequencyInfoDL->absoluteFrequencyPointA < 600000)
+      scs_scaling = scs_scaling*3;
+    if (scc->downlinkConfigCommon->frequencyInfoDL->absoluteFrequencyPointA > 2016666)
+      scs_scaling = scs_scaling>>2;
+    uint32_t absolute_diff = (*scc->downlinkConfigCommon->frequencyInfoDL->absoluteFrequencySSB - scc->downlinkConfigCommon->frequencyInfoDL->absoluteFrequencyPointA);
+
+    uint16_t ssb_start_symbol = get_ssb_start_symbol(band,scs_ssb,ssb_index);
+
+    get_type0_PDCCH_CSS_config_parameters(&mac->type0_PDCCH_CSS_config,
+                                          frame,
+                                          mac->mib,
+                                          nr_slots_per_frame[scs_ssb],
+                                          ssb_subcarrier_offset,
+                                          ssb_start_symbol,
+                                          scs_ssb,
+                                          frequency_range,
+                                          ssb_index,
+                                          absolute_diff/(12*scs_scaling)-10);
+
+
+    mac->type0_pdcch_ss_mux_pattern = mac->type0_PDCCH_CSS_config.type0_pdcch_ss_mux_pattern;
+    mac->type0_pdcch_ss_sfn_c = mac->type0_PDCCH_CSS_config.sfn_c;
+    mac->type0_pdcch_ss_n_c = mac->type0_PDCCH_CSS_config.n_c;
+  }
+
   mac->dl_config_request.sfn = mac->type0_PDCCH_CSS_config.frame;
   mac->dl_config_request.slot = (ssb_index>>1) + ((ssb_index>>4)<<1); // not valid for 240kHz SCS
 

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_bch.c

@@ -53,33 +53,7 @@
 #include "executables/softmodem-common.h"
 
 extern RAN_CONTEXT_t RC;
-extern uint8_t SSB_Table[38];
 
-// start symbols for SSB types A,B,C,D,E
-uint16_t symbol_ssb_AC[8]={2,8,16,22,30,36,44,50};
-uint16_t symbol_ssb_BD[64]={4,8,16,20,32,36,44,48,60,64,72,76,88,92,100,104,144,148,156,160,172,176,184,188,200,204,212,216,228,232,240,244,284,288,
-                            296,300,312,316,324,328,340,344,352,356,368,372,380,384,424,428,436,440,452,456,464,468,480,484,492,496,508,512,520,524};
-uint16_t symbol_ssb_E[64]={8,12,16,20,32,36,40,44,64,68,72,76,88,92,96,100,120,124,128,132,144,148,152,156,176,180,184,188,200,204,208,212,288,292,
-                           296,300,312,316,320,324,344,348,352,356,368,372,376,380,400,404,408,412,424,428,432,436,456,460,464,468,480,484,488,492};
-
-uint16_t get_ssb_start_symbol(const long band, NR_SubcarrierSpacing_t scs, int i_ssb) {
-
-  switch (scs) {
-    case NR_SubcarrierSpacing_kHz15:
-      return symbol_ssb_AC[i_ssb];  //type A
-    case NR_SubcarrierSpacing_kHz30:
-      if (band == 5 || band == 66)
-        return symbol_ssb_BD[i_ssb];  //type B
-      else
-        return symbol_ssb_AC[i_ssb];  //type C
-    case NR_SubcarrierSpacing_kHz120:
-      return symbol_ssb_BD[i_ssb];  //type D
-    case NR_SubcarrierSpacing_kHz240:
-      return symbol_ssb_E[i_ssb];
-    default:
-      AssertFatal(1 == 0, "SCS %ld not allowed for SSB \n",scs);
-  }
-}
 
 uint16_t get_ssboffset_pointa(NR_ServingCellConfigCommon_t *scc,const long band) {
 
@@ -229,6 +203,7 @@ void schedule_nr_mib(module_id_t module_idP, frame_t frameP, sub_frame_t slotP,
                                                         mib,
                                                         slots_per_frame,
                                                         ssbSubcarrierOffset,
+                                                        ssb_start_symbol,
                                                         scs,
                                                         FR1,
                                                         i_ssb,
@@ -254,6 +229,7 @@ void schedule_nr_mib(module_id_t module_idP, frame_t frameP, sub_frame_t slotP,
                                                         mib,
                                                         slots_per_frame,
                                                         ssbSubcarrierOffset,
+                                                        ssb_start_symbol,
                                                         scs,
                                                         FR1,
                                                         i_ssb,
@@ -279,6 +255,7 @@ void schedule_nr_mib(module_id_t module_idP, frame_t frameP, sub_frame_t slotP,
                                                         mib,
                                                         slots_per_frame,
                                                         ssbSubcarrierOffset,
+                                                        ssb_start_symbol,
                                                         scs,
                                                         FR2,
                                                         i_ssb,