feature,sched: allow setting initial DL CQI in enb.conf

lib/include/srsran/interfaces/enb_rrc_interface_types.h

@@ -59,7 +59,6 @@ struct cell_cfg_t {
   double                              ul_freq_hz;
   int                                 target_pucch_sinr_db;
   int                                 target_pusch_sinr_db;
-  uint32_t                            initial_dl_cqi;
   bool                                enable_phr_handling;
   int                                 min_phr_thres;
   asn1::rrc::mob_ctrl_info_s::t304_e_ t304;

lib/include/srsran/interfaces/sched_interface.h

@@ -64,6 +64,7 @@ public:
     uint32_t    min_tpc_tti_interval    = 1;
     float       ul_snr_avg_alpha        = 0.05;
     int         init_ul_snr_value       = 5;
+    int         init_dl_cqi             = 5;
   };
 
   struct cell_cfg_t {
@@ -100,7 +101,6 @@ public:
 
     uint32_t nrb_cqi;
     uint32_t ncs_an;
-    uint32_t initial_dl_cqi;
 
     uint32_t srs_subframe_config;
     uint32_t srs_subframe_offset;

srsenb/enb.conf.example

@@ -176,6 +176,7 @@ enable = false
 # min_tpc_tti_interval: Minimum TTI interval between TPCs different than 1
 # ul_snr_avg_alpha:  Exponential Average alpha coefficient used in estimation of UL SNR
 # init_ul_snr_value: Initial UL SNR value used for computing MCS in the first UL grant
+# init_dl_cqi:       DL CQI value used before any CQI report is available to the eNB
 #
 #####################################################################
 [scheduler]
@@ -198,6 +199,7 @@ enable = false
 #min_tpc_tti_interval = 1
 #ul_snr_avg_alpha=0.05
 #init_ul_snr_value=5
+#init_dl_cqi=5
 
 #####################################################################
 # eMBMS configuration options

srsenb/src/enb_cfg_parser.cc

@@ -758,7 +758,6 @@ static int parse_cell_list(all_args_t* args, rrc_cfg_t* rrc_cfg, Setting& root)
     parse_default_field(cell_cfg.ul_earfcn, cellroot, "ul_earfcn", 0u); // will be derived from DL EARFCN If not set
     parse_default_field(
         cell_cfg.root_seq_idx, cellroot, "root_seq_idx", rrc_cfg->sibs[1].sib2().rr_cfg_common.prach_cfg.root_seq_idx);
-    parse_default_field(cell_cfg.initial_dl_cqi, cellroot, "initial_dl_cqi", 5u);
     parse_default_field(cell_cfg.meas_cfg.meas_gap_period, cellroot, "meas_gap_period", 0u);
     if (cellroot.exists("meas_gap_offset_subframe")) {
       cell_cfg.meas_cfg.meas_gap_offset_subframe.resize(cellroot["meas_gap_offset_subframe"].getLength());

srsenb/src/main.cc

@@ -158,6 +158,7 @@ void parse_args(all_args_t* args, int argc, char* argv[])
     ("scheduler.min_tpc_tti_interval", bpo::value<uint32_t>(&args->stack.mac.sched.min_tpc_tti_interval)->default_value(1), "Minimum TTI interval between positive or negative TPCs")
     ("scheduler.ul_snr_avg_alpha", bpo::value<float>(&args->stack.mac.sched.ul_snr_avg_alpha)->default_value(0.05), "Exponential Average alpha coefficient used in estimation of UL SNR")
     ("scheduler.init_ul_snr_value", bpo::value<int>(&args->stack.mac.sched.init_ul_snr_value)->default_value(5), "Initial UL SNR value used for computing MCS in the first UL grant")
+    ("scheduler.init_dl_cqi", bpo::value<int>(&args->stack.mac.sched.init_dl_cqi)->default_value(5), "DL CQI value used before any CQI report is available to the eNB")
 
 
     /* Downlink Channel emulator section */

srsenb/src/stack/mac/sched_ue_ctrl/sched_ue_cell.cc

@@ -48,10 +48,8 @@ sched_ue_cell::sched_ue_cell(uint16_t rnti_, const sched_cell_params_t& cell_cfg
   fixed_mcs_ul(cell_cfg_.sched_cfg->pusch_mcs),
   current_tti(current_tti_),
   max_aggr_level(cell_cfg_.sched_cfg->max_aggr_level >= 0 ? cell_cfg_.sched_cfg->max_aggr_level : 3),
-  dl_cqi_ctxt(cell_cfg_.nof_prb(), 0, 1)
+  dl_cqi_ctxt(cell_cfg_.nof_prb(), 0, cell_cfg_.sched_cfg->init_dl_cqi)
 {
-  clear_feedback();
-
   float target_bler = cell_cfg->sched_cfg->target_bler;
   delta_inc         = cell_cfg->sched_cfg->adaptive_link_step_size; // delta_{down} of OLLA
   delta_dec         = (1 - target_bler) * delta_inc / target_bler;
@@ -157,7 +155,7 @@ void sched_ue_cell::clear_feedback()
   dl_ri_tti_rx  = tti_point{};
   dl_pmi        = 0;
   dl_pmi_tti_rx = tti_point{};
-  dl_cqi_ctxt.reset_cqi(ue_cc_idx == 0 ? cell_cfg->cfg.initial_dl_cqi : 1);
+  dl_cqi_ctxt.reset_cqi(ue_cc_idx == 0 ? cell_cfg->sched_cfg->init_dl_cqi : 1);
   ul_cqi_tti_rx = tti_point{};
 }
 

srsenb/src/stack/rrc/rrc.cc

@@ -646,7 +646,6 @@ void rrc::config_mac()
     item.prach_freq_offset    = cfg.sibs[1].sib2().rr_cfg_common.prach_cfg.prach_cfg_info.prach_freq_offset;
     item.maxharq_msg3tx       = cfg.sibs[1].sib2().rr_cfg_common.rach_cfg_common.max_harq_msg3_tx;
     item.enable_64qam         = cfg.sibs[1].sib2().rr_cfg_common.pusch_cfg_common.pusch_cfg_basic.enable64_qam;
-    item.initial_dl_cqi       = cfg.cell_list[ccidx].initial_dl_cqi;
     item.target_pucch_ul_sinr = cfg.cell_list[ccidx].target_pucch_sinr_db;
     item.target_pusch_ul_sinr = cfg.cell_list[ccidx].target_pusch_sinr_db;
     item.enable_phr_handling  = cfg.cell_list[ccidx].enable_phr_handling;

srsenb/test/mac/sched_test_utils.h

@@ -49,7 +49,6 @@ inline srsenb::sched_interface::cell_cfg_t generate_default_cell_cfg(uint32_t no
   cell_cfg.prach_freq_offset    = (cell_cfg_phy.nof_prb == 6) ? 0 : 4;
   cell_cfg.prach_rar_window     = 3;
   cell_cfg.maxharq_msg3tx       = 3;
-  cell_cfg.initial_dl_cqi       = 6;
   cell_cfg.target_pusch_ul_sinr = -1;
   cell_cfg.target_pucch_ul_sinr = -1;
   cell_cfg.enable_phr_handling  = false;