set minimum snr under which the UL SNR estimate is not updated

srsenb/hdr/stack/mac/sched_ue_ctrl/sched_ue_cell.h

@@ -43,6 +43,9 @@ struct sched_ue_cell {
   const sched_interface::ue_cfg_t* get_ue_cfg() const { return configured() ? ue_cfg : nullptr; }
   cc_st                            cc_state() const { return cc_state_; }
 
+  int set_ul_crc(tti_point tti_rx, bool crc_res);
+  int set_ul_snr(tti_point tti_rx, float ul_snr, uint32_t ul_ch_code);
+
   const uint16_t rnti;
 
   /// Cell const configuration

srsenb/hdr/stack/mac/sched_ue_ctrl/tpc.h

@@ -55,6 +55,11 @@ public:
 
   void set_snr(float snr, uint32_t ul_ch_code)
   {
+    static const float MIN_UL_SNR = -4.0f;
+    if (snr < MIN_UL_SNR) {
+      // Assume signal was not sent
+      return;
+    }
     if (ul_ch_code < nof_ul_ch_code) {
       snr_estim_list[ul_ch_code].pending_snr = snr;
     }

srsenb/src/stack/mac/sched_ue.cc

@@ -245,14 +245,7 @@ int sched_ue::set_ack_info(tti_point tti_rx, uint32_t enb_cc_idx, uint32_t tb_id
 
 void sched_ue::set_ul_crc(tti_point tti_rx, uint32_t enb_cc_idx, bool crc_res)
 {
-  if (cells[enb_cc_idx].cc_state() != cc_st::idle) {
-    int ret = cells[enb_cc_idx].harq_ent.set_ul_crc(tti_rx, 0, crc_res);
-    if (ret < 0) {
-      logger.warning("Received UL CRC for invalid tti_rx=%d", (int)tti_rx.to_uint());
-    }
-  } else {
-    logger.warning("Received UL CRC for invalid cell index %d", enb_cc_idx);
-  }
+  cells[enb_cc_idx].set_ul_crc(tti_rx, crc_res);
 }
 
 void sched_ue::set_dl_ri(tti_point tti_rx, uint32_t enb_cc_idx, uint32_t ri)
@@ -286,15 +279,7 @@ void sched_ue::set_dl_cqi(tti_point tti_rx, uint32_t enb_cc_idx, uint32_t cqi)
 
 void sched_ue::set_ul_snr(tti_point tti_rx, uint32_t enb_cc_idx, float snr, uint32_t ul_ch_code)
 {
-  if (cells[enb_cc_idx].cc_state() != cc_st::idle) {
-    cells[enb_cc_idx].tpc_fsm.set_snr(snr, ul_ch_code);
-    if (ul_ch_code == tpc::PUSCH_CODE) {
-      cells[enb_cc_idx].ul_cqi        = srsran_cqi_from_snr(snr);
-      cells[enb_cc_idx].ul_cqi_tti_rx = tti_rx;
-    }
-  } else {
-    logger.warning("Received SNR info for invalid cell index %d", enb_cc_idx);
-  }
+  cells[enb_cc_idx].set_ul_snr(tti_rx, snr, ul_ch_code);
 }
 
 /*******************************************************

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

@@ -16,6 +16,14 @@
 #include "srsenb/hdr/stack/mac/schedulers/sched_base.h"
 #include <numeric>
 
+#define CHECK_INVALID_FEEDBACK(feedback_type)                                                                          \
+  do {                                                                                                                 \
+    if (cc_state() == cc_st::idle) {                                                                                   \
+      logger.warning("SCHED: rnti=0x%x received " feedback_type " for idle cc=%d", cell_cfg->enb_cc_idx);              \
+      return SRSRAN_ERROR;                                                                                             \
+    }                                                                                                                  \
+  } while (0)
+
 namespace srsenb {
 
 /*******************************************************
@@ -160,6 +168,29 @@ void sched_ue_cell::set_dl_wb_cqi(tti_point tti_rx, uint32_t dl_cqi_)
   }
 }
 
+int sched_ue_cell::set_ul_crc(tti_point tti_rx, bool crc_res)
+{
+  CHECK_INVALID_FEEDBACK("UL CRC");
+  // Update HARQ process
+  int pid = harq_ent.set_ul_crc(tti_rx, 0, crc_res);
+  if (pid < 0) {
+    logger.warning("SCHED: rnti=0x%x received UL CRC for invalid tti_rx=%d", (int)tti_rx.to_uint());
+    return SRSRAN_ERROR;
+  }
+  return pid;
+}
+
+int sched_ue_cell::set_ul_snr(tti_point tti_rx, float ul_snr, uint32_t ul_ch_code)
+{
+  CHECK_INVALID_FEEDBACK("UL SNR estimate");
+  tpc_fsm.set_snr(ul_snr, ul_ch_code);
+  if (ul_ch_code == tpc::PUSCH_CODE) {
+    ul_cqi        = srsran_cqi_from_snr(ul_snr);
+    ul_cqi_tti_rx = tti_rx;
+  }
+  return SRSRAN_SUCCESS;
+}
+
 /*************************************************************
  *                    TBS/MCS derivation
  ************************************************************/