From 03db617c387ddd52bf5883888842168f509f1a1d Mon Sep 17 00:00:00 2001 From: Parminder Singh Date: Fri, 6 Nov 2020 11:44:18 +0100 Subject: [PATCH] Remove TX-GAIN multiplication with transmitted signal in ULSIM - Removed tx_gain calculations and multiplication with tx signal - Updated sigma value calculations and removed unused variables - Re-indent the related code for better readability --- openair1/SIMULATION/NR_PHY/ulsim.c | 72 ++++++++++++------------------ 1 file changed, 29 insertions(+), 43 deletions(-) diff --git a/openair1/SIMULATION/NR_PHY/ulsim.c b/openair1/SIMULATION/NR_PHY/ulsim.c index e48672dfde..af3c1a827b 100644 --- a/openair1/SIMULATION/NR_PHY/ulsim.c +++ b/openair1/SIMULATION/NR_PHY/ulsim.c @@ -162,8 +162,6 @@ int main(int argc, char **argv) FILE *input_fd = NULL; SCM_t channel_model = AWGN; //Rayleigh1_anticorr; uint16_t N_RB_DL = 106, N_RB_UL = 106, mu = 1; - double tx_gain=1.0; - double N0=30; //unsigned char frame_type = 0; NR_DL_FRAME_PARMS *frame_parms; @@ -177,7 +175,6 @@ int main(int argc, char **argv) int gNB_id = 0; int ap; int tx_offset; - double txlev_float; int32_t txlev; int start_rb = 0; int UE_id =0; // [hna] only works for UE_id = 0 because NUMBER_OF_NR_UE_MAX is set to 1 (phy_init_nr_gNB causes segmentation fault) @@ -953,8 +950,6 @@ int main(int argc, char **argv) nr_fill_ulsch(gNB,frame,slot,pusch_pdu); for (int i=0;i<(TBS/8);i++) ulsch_ue[0]->harq_processes[harq_pid]->a[i]=i&0xff; - double scale = 1; - if (input_fd == NULL) { // set FAPI parameters for UE, put them in the scheduled response and call @@ -977,48 +972,39 @@ int main(int argc, char **argv) txlev = signal_energy(&UE->common_vars.txdata[0][tx_offset + 5*frame_parms->ofdm_symbol_size + 4*frame_parms->nb_prefix_samples + frame_parms->nb_prefix_samples0], frame_parms->ofdm_symbol_size + frame_parms->nb_prefix_samples); - - txlev_float = (double)txlev/scale; // output of signal_energy is fixed point representation - - } else n_trials = 1; - if (input_fd == NULL ) { - - sigma_dB = N0; - sigma = pow(10,sigma_dB/10); - - tx_gain = sqrt(pow(10.0,.1*(N0+SNR))/txlev_float); - if(n_trials==1) printf("txlev_float %f, sigma_dB %f, tx_gain %f tx_offset %d, slot_offset %d\n",10*log10(txlev_float),sigma_dB,tx_gain,tx_offset,slot_offset); - - for (i=0; icommon_vars.txdata[aa][slot_offset]))[(i<<1)]); - s_im[aa][i] = ((double)(((short *)&UE->common_vars.txdata[aa][slot_offset]))[(i<<1)+1]); - } - } - - - if (UE2gNB->max_Doppler == 0) { - multipath_channel(UE2gNB,s_re,s_im,r_re,r_im, - slot_length,0,(n_trials==1)?1:0); - } else { - multipath_tv_channel(UE2gNB,s_re,s_im,r_re,r_im, - 2*slot_length,0); - } - for (i=0; inb_antennas_rx; ap++) { - ((int16_t*) &gNB->common_vars.rxdata[ap][slot_offset])[(2*i) + (delay*2)] = (int16_t)((tx_gain*r_re[ap][i]) + (sqrt(sigma/2)*gaussdouble(0.0,1.0))); // convert to fixed point - ((int16_t*) &gNB->common_vars.rxdata[ap][slot_offset])[(2*i)+1 + (delay*2)] = (int16_t)((tx_gain*r_im[ap][i]) + (sqrt(sigma/2)*gaussdouble(0.0,1.0))); - /* Add phase noise if enabled */ - if (pdu_bit_map & PUSCH_PDU_BITMAP_PUSCH_PTRS) { - phase_noise(ts, &((int16_t*)&gNB->common_vars.rxdata[ap][slot_offset])[(2*i)], - &((int16_t*)&gNB->common_vars.rxdata[ap][slot_offset])[(2*i)+1]); - } - } - } + if (input_fd == NULL ) + { + sigma_dB = 10 * log10((double)txlev * ((double)frame_parms->ofdm_symbol_size/(12*nb_rb))) - SNR; + sigma = pow(10,sigma_dB/10); + if (n_trials==1) printf("sigma %f (%f dB), txlev %f (factor %f)\n",sigma,sigma_dB,10*log10((double)txlev),(double)(double)frame_parms->ofdm_symbol_size/(12*nb_rb)); + for (i=0; icommon_vars.txdata[aa][slot_offset]))[(i<<1)]); + s_im[aa][i] = ((double)(((short *)&UE->common_vars.txdata[aa][slot_offset]))[(i<<1)+1]); + } + } + if (UE2gNB->max_Doppler == 0) { + multipath_channel(UE2gNB,s_re,s_im,r_re,r_im, + slot_length,0,(n_trials==1)?1:0); + } else { + multipath_tv_channel(UE2gNB,s_re,s_im,r_re,r_im, + 2*slot_length,0); + } + for (i=0; inb_antennas_rx; ap++) { + ((int16_t*) &gNB->common_vars.rxdata[ap][slot_offset])[(2*i) + (delay*2)] = (int16_t)(r_re[ap][i] + (sqrt(sigma/2)*gaussdouble(0.0,1.0))); // convert to fixed point + ((int16_t*) &gNB->common_vars.rxdata[ap][slot_offset])[(2*i)+1 + (delay*2)] = (int16_t)(r_im[ap][i] + (sqrt(sigma/2)*gaussdouble(0.0,1.0))); + /* Add phase noise if enabled */ + if (pdu_bit_map & PUSCH_PDU_BITMAP_PUSCH_PTRS) { + phase_noise(ts, &((int16_t*)&gNB->common_vars.rxdata[ap][slot_offset])[(2*i)], + &((int16_t*)&gNB->common_vars.rxdata[ap][slot_offset])[(2*i)+1]); + } + } + } } if(pusch_pdu->pdu_bit_map & PUSCH_PDU_BITMAP_PUSCH_PTRS)