Removed cached PRACH signals

srsue/hdr/phy/prach.h

@@ -41,16 +41,6 @@ public:
 private:
   bool generate_buffer(uint32_t f_idx);
 
-  bool is_buffer_generated(uint32_t f_idx, uint32_t preamble_index) const
-  {
-    return buffer_bitmask.test(f_idx * 64 + preamble_index);
-  }
-
-  void set_buffer_as_generated(uint32_t f_idx, uint32_t preamble_index)
-  {
-    buffer_bitmask.set(f_idx * 64 + preamble_index);
-  }
-
 private:
   static constexpr unsigned MAX_LEN_SF    = 3;
   static constexpr unsigned max_fs        = 12;
@@ -61,7 +51,6 @@ private:
   srsran_cell_t         cell             = {};
   srsran_cfo_t          cfo_h            = {};
   srsran_prach_cfg_t    cfg              = {};
-  std::array<std::array<cf_t*, max_preambles>, max_fs> buffer           = {};
   cf_t*                 signal_buffer    = nullptr;
   int                   preamble_idx     = -1;
   uint32_t              len              = 0;
@@ -70,7 +59,6 @@ private:
   float                 target_power_dbm = 0;
   bool                  mem_initiated    = false;
   bool                  cell_initiated   = false;
-  std::bitset<max_fs * max_preambles>                  buffer_bitmask;
   mutable std::mutex    mutex;
 };
 

srsue/src/phy/prach.cc

@@ -33,15 +33,6 @@ using namespace srsue;
 void prach::init(uint32_t max_prb)
 {
   std::lock_guard<std::mutex> lock(mutex);
-  for (auto& i : buffer) {
-    for (auto& j : i) {
-      j = srsran_vec_cf_malloc(SRSRAN_PRACH_MAX_LEN);
-      if (!j) {
-        perror("malloc");
-        return;
-      }
-    }
-  }
 
   if (srsran_cfo_init(&cfo_h, SRSRAN_PRACH_MAX_LEN)) {
     ERROR("PRACH: Error initiating CFO");
@@ -50,7 +41,7 @@ void prach::init(uint32_t max_prb)
 
   srsran_cfo_set_tol(&cfo_h, 0);
 
-  signal_buffer = srsran_vec_cf_malloc(MAX_LEN_SF * 30720U);
+  signal_buffer = srsran_vec_cf_malloc(SRSRAN_MAX(MAX_LEN_SF * 30720U, SRSRAN_PRACH_MAX_LEN));
   if (!signal_buffer) {
     perror("malloc");
     return;
@@ -71,12 +62,6 @@ void prach::stop()
     return;
   }
 
-  for (auto& i : buffer) {
-    for (auto& j : i) {
-      free(j);
-    }
-  }
-
   free(signal_buffer);
   srsran_cfo_free(&cfo_h);
   srsran_prach_free(&prach_obj);
@@ -118,7 +103,6 @@ bool prach::set_cell(srsran_cell_t cell_, srsran_prach_cfg_t prach_cfg)
     return false;
   }
 
-  buffer_bitmask.reset();
   len             = prach_obj.N_seq + prach_obj.N_cp;
   transmitted_tti = -1;
   cell_initiated  = true;
@@ -130,22 +114,16 @@ bool prach::set_cell(srsran_cell_t cell_, srsran_prach_cfg_t prach_cfg)
 
 bool prach::generate_buffer(uint32_t f_idx)
 {
-  if (is_buffer_generated(f_idx, preamble_idx)) {
-    return true;
-  }
-
   uint32_t freq_offset = cfg.freq_offset;
   if (cell.frame_type == SRSRAN_TDD) {
     freq_offset = srsran_prach_f_ra_tdd(
         cfg.config_idx, cfg.tdd_config.sf_config, (f_idx / 6) * 10, f_idx % 6, cfg.freq_offset, cell.nof_prb);
   }
-  if (srsran_prach_gen(&prach_obj, preamble_idx, freq_offset, buffer[f_idx][preamble_idx])) {
+  if (srsran_prach_gen(&prach_obj, preamble_idx, freq_offset, signal_buffer)) {
     Error("Generating PRACH preamble %d", preamble_idx);
     return false;
   }
 
-  set_buffer_as_generated(f_idx, preamble_idx);
-
   return true;
 }
 
@@ -239,13 +217,8 @@ cf_t* prach::generate(float cfo, uint32_t* nof_sf, float* target_power)
     return nullptr;
   }
 
-  if (!is_buffer_generated(f_idx, preamble_idx)) {
-    Error("PRACH Buffer not generated: f_idx=%d preamble_idx=%d", f_idx, preamble_idx);
-    return nullptr;
-  }
-
   // Correct CFO before transmission
-  srsran_cfo_correct(&cfo_h, buffer[f_idx][preamble_idx], signal_buffer, cfo / srsran_symbol_sz(cell.nof_prb));
+  srsran_cfo_correct(&cfo_h, signal_buffer, signal_buffer, cfo / srsran_symbol_sz(cell.nof_prb));
 
   // pad guard symbols with zeros
   uint32_t nsf = SRSRAN_CEIL(len, SRSRAN_SF_LEN_PRB(cell.nof_prb));