Fixed TA symbol time

lte/examples/prach_ue.c

@@ -469,7 +469,7 @@ int main(int argc, char **argv) {
               
               uint32_t ul_sf_idx = (ue_sync_get_sfidx(&ue_sync)+6)%10;
 
-              ue_ul_set_cfo(&ue_ul, sync_get_cfo(&ue_sync.strack));
+              //ue_ul_set_cfo(&ue_ul, sync_get_cfo(&ue_sync.strack));
               bit_pack_vector((uint8_t*) conn_request_msg, data, ra_pusch.mcs.tbs);
               n = ue_ul_pusch_encode_rnti(&ue_ul, &ra_pusch, data, ul_sf_idx, rar_msg.temp_c_rnti, ul_signal);
               if (n < 0) {
@@ -492,12 +492,12 @@ int main(int argc, char **argv) {
 
               uint32_t n_ta = lte_N_ta_new_rar(rar_msg.timing_adv_cmd);
               printf("ta: %d, n_ta: %d\n", rar_msg.timing_adv_cmd, n_ta);
-              float time_adv_sec = ((float) n_ta)*TS_PRB(cell.nof_prb);
+              float time_adv_sec = ((float) n_ta)*LTE_TS;
               
-              vec_sc_prod_cfc(ul_signal, 20, ul_signal, SF_LEN_PRB(cell.nof_prb));
+              vec_sc_prod_cfc(ul_signal, 2, ul_signal, SF_LEN_PRB(cell.nof_prb));
 
-              timestamp_copy(&next_tx_time, &uhd_time);
               
+              timestamp_copy(&next_tx_time, &uhd_time);
               timestamp_add(&next_tx_time, 0, 0.006 - time_adv_sec); // send after 6 sub-frames (6 ms)
               printf("Send %d samples PUSCH sfn: %d. Last frame time = %.6f"
                     "send PUSCH time = %.6f TA: %.1f us\n", 
@@ -506,6 +506,7 @@ int main(int argc, char **argv) {
               cuhd_send_timed(uhd, ul_signal, SF_LEN_PRB(cell.nof_prb),
                             next_tx_time.full_secs, next_tx_time.frac_secs);                
              
+              vec_save_file("prach_example_signal", ul_signal, sizeof(cf_t)*7680);
               go_exit = 1; 
             }
             if (sfn >= rar_window_stop) {              

lte/phy/include/liblte/phy/common/phy_common.h

@@ -98,9 +98,7 @@ typedef enum {CPNORM, CPEXT} lte_cp_t;
 #define SLOT_LEN_RE(nof_prb, cp)        (nof_prb*RE_X_RB*CP_NSYMB(cp))
 #define SF_LEN_RE(nof_prb, cp)          (2*SLOT_LEN_RE(nof_prb, cp))
 
-#define TS_SYMBOLSZ(symbol_sz)  (1.0/(15000.0*symbol_sz))
-#define TS_PRB(nof_prb)         TS_SYMBOLSZ(lte_symbol_sz(nof_prb))
-
+#define LTE_TS         1.0/(15000.0*2048)
 
 #define SLOT_IDX_CPNORM(symbol_idx, symbol_sz) (symbol_idx==0?0:(symbol_sz + CP(symbol_sz, CPNORM_0_LEN) + \
                                                 (symbol_idx-1)*(symbol_sz+CP(symbol_sz, CPNORM_LEN))))