Improved neighbour cell accuracy. Changed RRC to avoid segfault when …

…neighbour cell addition

lib/include/srslte/interfaces/ue_interfaces.h

@@ -161,7 +161,7 @@ class rrc_interface_phy
   virtual void out_of_sync() = 0;
   virtual void earfcn_end() = 0;
   virtual void cell_found(uint32_t earfcn, srslte_cell_t phy_cell, float rsrp) = 0;
-  virtual void new_phy_meas(float rsrp, float rsrq, uint32_t tti, uint32_t earfcn = 0, uint32_t pci = 0) = 0;
+  virtual void new_phy_meas(float rsrp, float rsrq, uint32_t tti, int earfcn = -1, int pci = -1) = 0;
 };
 
 // RRC interface for NAS

lib/include/srslte/phy/utils/ringbuffer.h

@@ -5,9 +5,11 @@
 #include "srslte/config.h"
 #include <pthread.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 typedef struct {
-  uint8_t *buffer; 
+  uint8_t *buffer;
+  bool active;
   int capacity; 
   int count; 
   int wpm; 
@@ -34,6 +36,7 @@ SRSLTE_API int  srslte_ringbuffer_read(srslte_ringbuffer_t *q,
                                        void *ptr,
                                        int nof_bytes);
 
+SRSLTE_API void srslte_ringbuffer_stop(srslte_ringbuffer_t *q);
 
 #endif
 

lib/src/phy/phch/pdcch.c

@@ -293,9 +293,10 @@ uint32_t srslte_pdcch_common_locations_ncce(uint32_t nof_cce, srslte_dci_locatio
   for (l = 3; l > 1; l--) {
     L = (1 << l);
     for (i = 0; i < SRSLTE_MIN(nof_cce, 16) / (L); i++) {
-      if (k < max_candidates) {
-        c[k].L = l;
-        c[k].ncce = (L) * (i % (nof_cce / (L)));
+      uint32_t ncce = (L) * (i % (nof_cce / (L)));
+      if (k < max_candidates && ncce + L <= nof_cce) {
+        c[k].L    = l;
+        c[k].ncce = ncce;
         DEBUG("Common SS Candidate %d: nCCE: %d, L: %d\n",
             k, c[k].ncce, c[k].L);
         k++;

lib/src/phy/sync/sync.c

@@ -71,7 +71,7 @@ int srslte_sync_init_decim(srslte_sync_t *q, uint32_t frame_size, uint32_t max_o
     q->N_id_1 = 1000;
 
     q->cfo_ema_alpha = CFO_EMA_ALPHA;
-    q->sss_alg = SSS_FULL;
+    q->sss_alg = SSS_PARTIAL_3;
 
     q->detect_cp       = true;
     q->sss_en          = true;

lib/src/phy/ue/ue_dl.c

@@ -910,7 +910,7 @@ static int find_dl_dci_type_crnti(srslte_ue_dl_t *q, uint32_t tm, uint32_t cfi,
 
     current_ss->format = format;
     if ((ret = dci_blind_search(q, current_ss, rnti, cfi, dci_msg))) {
-      return ret; 
+      return ret;
     }
   }
 

lib/src/phy/utils/ringbuffer.c

@@ -11,7 +11,7 @@ int srslte_ringbuffer_init(srslte_ringbuffer_t *q, int capacity)
   if (!q->buffer) {
     return -1; 
   }
-
+  q->active     = true;
   q->capacity   = capacity;
   srslte_ringbuffer_reset(q);
 
@@ -24,6 +24,7 @@ int srslte_ringbuffer_init(srslte_ringbuffer_t *q, int capacity)
 void srslte_ringbuffer_free(srslte_ringbuffer_t *q)
 {
   if (q) {
+    srslte_ringbuffer_stop(q);
     if (q->buffer) {
       free(q->buffer);
       q->buffer = NULL; 
@@ -52,6 +53,9 @@ int srslte_ringbuffer_write(srslte_ringbuffer_t *q, void *p, int nof_bytes)
   uint8_t *ptr = (uint8_t*) p;
   int w_bytes = nof_bytes;
   pthread_mutex_lock(&q->mutex);
+  if (!q->active) {
+    return 0;
+  }
   if (q->count + w_bytes > q->capacity) {
     w_bytes = q->capacity - q->count; 
     fprintf(stderr, "Buffer overrun: lost %d bytes\n", nof_bytes - w_bytes);
@@ -77,9 +81,12 @@ int srslte_ringbuffer_read(srslte_ringbuffer_t *q, void *p, int nof_bytes)
 {
   uint8_t *ptr = (uint8_t*) p;
   pthread_mutex_lock(&q->mutex);
-  while(q->count < nof_bytes) {
+  while(q->count < nof_bytes && q->active) {
     pthread_cond_wait(&q->cvar, &q->mutex);
   }
+  if (!q->active) {
+    return 0;
+  }
   if (nof_bytes + q->rpm > q->capacity) {
     int x = q->capacity - q->rpm; 
     memcpy(ptr, &q->buffer[q->rpm], x);
@@ -96,5 +103,9 @@ int srslte_ringbuffer_read(srslte_ringbuffer_t *q, void *p, int nof_bytes)
   return nof_bytes; 
 }
 
-
+void srslte_ringbuffer_stop(srslte_ringbuffer_t *q) {
+  pthread_mutex_lock(&q->mutex);
+  pthread_cond_broadcast(&q->cvar);
+  pthread_mutex_unlock(&q->mutex);
+}
 

srsue/hdr/mac/mac.h

@@ -113,7 +113,7 @@ class mac
   void run_thread(); 
 
   static const int MAC_MAIN_THREAD_PRIO = -1; // Use default high-priority below UHD
-  static const int MAC_PDU_THREAD_PRIO  = -1;
+  static const int MAC_PDU_THREAD_PRIO  = DEFAULT_PRIORITY-5;
   static const int MAC_NOF_HARQ_PROC    = 2*HARQ_DELAY_MS;
 
   // Interaction with PHY 

srsue/hdr/phy/phch_recv.h

@@ -166,7 +166,7 @@ class phch_recv : public thread, public chest_feedback_itf
     typedef enum {IDLE, MEASURE_OK, ERROR} ret_code;
 
     ~measure();
-    void      init(cf_t *buffer[SRSLTE_MAX_PORTS], srslte::log *log_h,
+    void      init(cf_t *buffer[SRSLTE_MAX_PORTS], srslte::log *log_h, srslte::radio *radio_h,
                    uint32_t nof_rx_antennas, uint32_t nof_subframes = RSRP_MEASURE_NOF_FRAMES);
     void      reset();
     void      set_cell(srslte_cell_t cell);
@@ -182,11 +182,12 @@ class phch_recv : public thread, public chest_feedback_itf
     srslte::log      *log_h;
     srslte_ue_dl_t    ue_dl;
     cf_t              *buffer[SRSLTE_MAX_PORTS];
+    srslte::radio    *radio_h;
     uint32_t cnt;
     uint32_t nof_subframes;
     uint32_t current_prb;
     float rx_gain_offset;
-    float mean_rsrp, mean_rsrq, mean_snr;
+    float mean_rsrp, mean_rsrq, mean_snr, mean_rssi;
     uint32_t final_offset;
     const static int RSRP_MEASURE_NOF_FRAMES = 5;
   };
@@ -201,13 +202,11 @@ class phch_recv : public thread, public chest_feedback_itf
       float    rsrq;
       uint32_t offset;
     } cell_info_t;
-    void init(srslte::log *log_h, bool sic_pss_enabled);
+    void init(srslte::log *log_h, bool sic_pss_enabled, uint32_t max_sf_window);
     void reset();
     int find_cells(cf_t *input_buffer, float rx_gain_offset, srslte_cell_t current_cell, uint32_t nof_sf, cell_info_t found_cells[MAX_CELLS]);
   private:
 
-    const static int DEFAULT_MEASUREMENT_LEN = 10;
-
     cf_t               *input_cfo_corrected;
     cf_t               *sf_buffer[SRSLTE_MAX_PORTS];
     srslte::log        *log_h;
@@ -235,8 +234,10 @@ class phch_recv : public thread, public chest_feedback_itf
     void write(uint32_t tti, cf_t *data, uint32_t nsamples);
   private:
     void run_thread();
-    const static int CAPTURE_LEN_SF = 15;
+    const static int INTRA_FREQ_MEAS_LEN_MS    = 20;
     const static int INTRA_FREQ_MEAS_PERIOD_MS = 200;
+    const static int INTRA_FREQ_MEAS_PRIO      = DEFAULT_PRIORITY + 5;
+
     scell_recv         scell;
     rrc_interface_phy  *rrc;
     srslte::log        *log_h;
@@ -260,6 +261,8 @@ class phch_recv : public thread, public chest_feedback_itf
     srslte_ringbuffer_t ring_buffer;
   };
 
+  // 36.133 9.1.2.1 for band 7
+  const static float ABSOLUTE_RSRP_THRESHOLD_DBM = -125;
 
 
   // Objects for internal use

srsue/hdr/upper/rrc.h

@@ -51,6 +51,58 @@ using srslte::byte_buffer_t;
 
 namespace srsue {
 
+
+class cell_t
+{
+ public:
+  bool is_valid() {
+    return earfcn != 0 && srslte_cell_isvalid(&phy_cell);
+  }
+  bool equals(cell_t *x) {
+    return equals(x->earfcn, x->phy_cell.id);
+  }
+  bool equals(uint32_t earfcn, uint32_t pci) {
+    return earfcn == this->earfcn && pci == phy_cell.id;
+  }
+  bool greater(cell_t *x) {
+    return x->rsrp > rsrp;
+  }
+  bool plmn_equals(LIBLTE_RRC_PLMN_IDENTITY_STRUCT plmn_id) {
+    for (uint32_t i = 0; i < sib1.N_plmn_ids; i++) {
+      if (plmn_id.mcc == sib1.plmn_id[i].id.mcc && plmn_id.mnc == sib1.plmn_id[i].id.mnc) {
+        return true;
+      }
+    }
+    return false;
+  }
+  cell_t() {
+    this->has_valid_sib1 = false;
+    this->has_valid_sib2 = false;
+    this->has_valid_sib3 = false;
+  }
+  cell_t(srslte_cell_t phy_cell, uint32_t earfcn, float rsrp) {
+    this->has_valid_sib1 = false;
+    this->has_valid_sib2 = false;
+    this->has_valid_sib3 = false;
+    this->phy_cell = phy_cell;
+    this->rsrp = rsrp;
+    this->earfcn = earfcn;
+  }
+
+  uint32_t earfcn;
+  srslte_cell_t phy_cell;
+  float    rsrp;
+  bool     has_valid_sib1;
+  bool     has_valid_sib2;
+  bool     has_valid_sib3;
+  bool     has_valid_sib13;
+  bool     in_sync;
+  LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_1_STRUCT  sib1;
+  LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_2_STRUCT  sib2;
+  LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_3_STRUCT  sib3;
+  LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_13_STRUCT sib13;
+};
+
 class rrc
   :public rrc_interface_nas
   ,public rrc_interface_phy
@@ -100,7 +152,7 @@ class rrc
   void out_of_sync();
   void earfcn_end();
   void cell_found(uint32_t earfcn, srslte_cell_t phy_cell, float rsrp);
-  void new_phy_meas(float rsrp, float rsrq, uint32_t tti, uint32_t earfcn, uint32_t pci);
+  void new_phy_meas(float rsrp, float rsrq, uint32_t tti, int earfcn, int pci);
 
   // MAC interface
   void ho_ra_completed(bool ra_successful);
@@ -154,7 +206,7 @@ class rrc
   bool first_stimsi_attempt;
 
   uint16_t ho_src_rnti;
-  int      ho_src_cell_idx;
+  cell_t   ho_src_cell;
   phy_interface_rrc::phy_cfg_t ho_src_phy_cfg;
   mac_interface_rrc::mac_cfg_t ho_src_mac_cfg;
   bool pending_mob_reconf;
@@ -215,28 +267,18 @@ class rrc
     }
   }
 
-  typedef struct {
-    uint32_t earfcn;
-    srslte_cell_t phy_cell;
-    float    rsrp;
-    bool     has_valid_sib1;
-    bool     has_valid_sib2;
-    bool     has_valid_sib3;
-    bool     has_valid_sib13;
-    bool     in_sync;
-    LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_1_STRUCT  sib1;
-    LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_2_STRUCT  sib2;
-    LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_3_STRUCT  sib3;
-    LIBLTE_RRC_SYS_INFO_BLOCK_TYPE_13_STRUCT sib13;
-  } cell_t;
-
-  const static int MAX_KNOWN_CELLS = 64;
-  cell_t known_cells[MAX_KNOWN_CELLS];
-  cell_t *current_cell;
-
-  int        find_cell_idx(uint32_t earfcn, uint32_t pci);
-  cell_t*    add_new_cell(uint32_t earfcn, srslte_cell_t phy_cell, float rsrp);
-  uint32_t   find_best_cell(uint32_t earfcn, srslte_cell_t *cell);
+  // List of strongest neighbour cell
+  const static int NOF_NEIGHBOUR_CELLS = 8;
+  std::vector<cell_t*> neighbour_cells;
+  cell_t *serving_cell;
+  void set_serving_cell(uint32_t cell_idx);
+  void set_serving_cell(uint32_t earfcn, uint32_t pci);
+
+  int  find_neighbour_cell(uint32_t earfcn, uint32_t pci);
+  bool add_neighbour_cell(uint32_t earfcn, uint32_t pci, float rsrp);
+  bool add_neighbour_cell(uint32_t earfcn, srslte_cell_t phy_cell, float rsrp);
+  bool add_neighbour_cell(cell_t *cell);
+  void sort_neighbour_cells();
 
   typedef enum {
     SI_ACQUIRE_IDLE = 0,
@@ -253,7 +295,6 @@ class rrc
 
   void select_next_cell_in_plmn();
   LIBLTE_RRC_PLMN_IDENTITY_STRUCT selected_plmn_id;
-  int last_selected_cell;
 
   bool thread_running;
   void run_thread();
@@ -395,10 +436,10 @@ class rrc
   // Helpers
   void          ho_failed();
   bool          ho_prepare();
-  void          add_neighbour_cell(uint32_t earfcn, uint32_t pci, float rsrp);
   void          rrc_connection_release();
   void          con_restablish_cell_reselected();
   void          radio_link_failure();
+  void          leave_connected();
 
   static void*  start_sib_thread(void *rrc_);
   void          sib_search();

srsue/src/main.cc

@@ -242,7 +242,7 @@ void parse_args(all_args_t *args, int argc, char *argv[]) {
      "After the PSS estimation is below cfo_loop_pss_tol for cfo_loop_pss_timeout times consecutively, RS adjustments are allowed.")
 
     ("expert.sic_pss_enabled",
-     bpo::value<bool>(&args->expert.phy.sic_pss_enabled)->default_value(true),
+     bpo::value<bool>(&args->expert.phy.sic_pss_enabled)->default_value(false),
      "Applies Successive Interference Cancellation to PSS signals when searching for neighbour cells. Must be disabled if cells have identical channel and timing.")
 
     ("expert.average_subframe_enabled",