remove SL specific CFO correction method

lib/include/srslte/phy/sync/cfo.h

@@ -62,6 +62,4 @@ srslte_cfo_correct_offset(srslte_cfo_t* h, const cf_t* input, cf_t* output, floa
 
 SRSLTE_API float srslte_cfo_est_corr_cp(cf_t* input_buffer, uint32_t nof_prb);
 
-SRSLTE_API float srslte_sl_cfo_est_corr_cp(cf_t* input_buffer, uint32_t nof_prb, srslte_cp_t cp);
-
 #endif // SRSLTE_CFO_H

lib/src/phy/phch/test/pscch_file_test.c

@@ -238,8 +238,7 @@ int main(int argc, char** argv)
       nread = -1;
     }
 
-    // CFO estimation and correction
-    srslte_sl_cfo_est_corr_cp(input_buffer, cell.nof_prb, cell.cp);
+    // Convert to frequency domain
     srslte_ofdm_rx_sf(&fft);
 
     if (cell.tm == SRSLTE_SIDELINK_TM1 || cell.tm == SRSLTE_SIDELINK_TM2) {

lib/src/phy/sync/cfo.c

@@ -147,49 +147,3 @@ float srslte_cfo_est_corr_cp(cf_t* input_buffer, uint32_t nof_prb)
   srslte_vec_apply_cfo(input_buffer, (float)(1 / (nFFT * 15e3)) * ((-15e3 / 2.0) - cfo), input_buffer, sf_n_samples);
   return cfo;
 }
-
-/*
- * Sidelink CFO estimation and correction based on cp
- */
-float srslte_sl_cfo_est_corr_cp(cf_t* input_buffer, uint32_t nof_prb, srslte_cp_t cp)
-{
-  int   symbol_sz    = srslte_symbol_sz(nof_prb);
-  int   sf_n_samples = SRSLTE_SF_LEN_PRB(nof_prb);
-  float tFFT         = (float)(1 / 15000.0);
-  int   cp_size      = SRSLTE_CP_SZ(symbol_sz, cp);
-  int   cp_size_0    = (cp == SRSLTE_CP_NORM) ? SRSLTE_CP_LEN_NORM(0, symbol_sz) : cp_size;
-
-  // Compensate for initial SC-FDMA half subcarrier shift, cfo = 7500 / (15000 * symbol_sz) <=> 1 / (symbol_sz * 2.0)
-  srslte_vec_apply_cfo(input_buffer, (1 / (float)(symbol_sz * 2.0)), input_buffer, sf_n_samples);
-
-  uint32_t p1     = 0;
-  uint32_t p2     = symbol_sz;
-  uint32_t cp_len = 0;
-
-  uint32_t sf_n_symbols = (cp == SRSLTE_CP_NORM)
-                              ? (14 - 1)
-                              : (12 - 1); // // TS 36.211 Section 9.3.2: The last SC-FDMA symbol in a sidelink subframe,
-                                          // serves as a guard period and shall not be used for sidelink transmission.
-
-  cf_t average_cfo = 0.0f;
-
-  for (int i = 0; i < sf_n_symbols; i++) {
-    // Calculate CP length
-    cp_len = (i == 0 || i == SRSLTE_CP_NSYMB(cp)) ? cp_size_0 : cp_size;
-
-    // Correlate CP with tail
-    average_cfo += srslte_vec_dot_prod_conj_ccc(&input_buffer[p2], &input_buffer[p1], cp_len);
-
-    // Increment pointers for next symbol
-    p1 += cp_len + symbol_sz;
-    p2 += cp_len + symbol_sz;
-  }
-
-  float cfo = (float)(carg(average_cfo) / (float)(2 * M_PI * tFFT));
-
-  // Compensate for initial SC-FDMA half subcarrier shift, cfo = - 7500 / (15000 * symbol_sz) <=> 1 / (symbol_sz * 2.0)
-  srslte_vec_apply_cfo(
-      input_buffer, (-1 / (float)(symbol_sz * 2.0)) + (-cfo / (float)(15e3 * symbol_sz)), input_buffer, sf_n_samples);
-
-  return cfo;
-}