From a752f43ad60371b0d27dfa52fe5db39813ef7ea3 Mon Sep 17 00:00:00 2001 From: Rakesh Mundlamuri Date: Wed, 31 Dec 2025 16:38:02 +0530 Subject: [PATCH] Harmonize phy_simulators to use compute_tx_energy_level() and compute_noise_variance() --- openair1/PHY/TOOLS/signal_energy.c | 11 ++++++-- openair1/PHY/TOOLS/tools_defs.h | 7 ++++- openair1/SIMULATION/NR_PHY/dlsim.c | 25 ++++++++--------- openair1/SIMULATION/NR_PHY/prachsim.c | 11 ++------ openair1/SIMULATION/NR_PHY/pucchsim.c | 24 ++++++++++++----- openair1/SIMULATION/NR_PHY/srssim.c | 2 +- openair1/SIMULATION/NR_PHY/ulsim.c | 39 +++++++++------------------ 7 files changed, 58 insertions(+), 61 deletions(-) diff --git a/openair1/PHY/TOOLS/signal_energy.c b/openair1/PHY/TOOLS/signal_energy.c index 9b50b947c3..4e29f0ab2b 100644 --- a/openair1/PHY/TOOLS/signal_energy.c +++ b/openair1/PHY/TOOLS/signal_energy.c @@ -196,9 +196,16 @@ double compute_tx_energy_level(c16_t **txdata, int nb_antennas, int offset, int } // Computes noise variance from the input transmit energy and SNR -double compute_noise_variance(double txlev_sum, uint16_t ofdm_symbol_size, int N_RB, double SNR, int n_trials) +double compute_noise_variance(double txlev_sum, + uint16_t ofdm_symbol_size, + int N_RB, + uint8_t precod_nbr_layers, + double SNR, + int n_trials) { - double sigma_dB = 10 * log10(txlev_sum * ((double)ofdm_symbol_size / (12 * N_RB))) - SNR; + // Justification of division by precod_nbr_layers: + // When the channel is the identity matrix, the results in terms of SNR should be almost equal for 2x2 and 4x4. + double sigma_dB = 10 * log10(txlev_sum / precod_nbr_layers * ((double)ofdm_symbol_size / (12 * N_RB))) - SNR; double sigma = pow(10, sigma_dB / 10); if (n_trials == 1) diff --git a/openair1/PHY/TOOLS/tools_defs.h b/openair1/PHY/TOOLS/tools_defs.h index 2f7bd438d6..36fc496545 100644 --- a/openair1/PHY/TOOLS/tools_defs.h +++ b/openair1/PHY/TOOLS/tools_defs.h @@ -929,7 +929,12 @@ double signal_energy_fp2(struct complexd *s, uint32_t length); double compute_tx_energy_level(c16_t **txdata, int nb_antennas, int offset, int length, int n_trials); -double compute_noise_variance(double txlev_sum, uint16_t ofdm_symbol_size, int N_RB, double SNR, int n_trials); +double compute_noise_variance(double txlev_sum, + uint16_t ofdm_symbol_size, + int N_RB, + uint8_t precod_nbr_layers, + double SNR, + int n_trials); int32_t iSqrt(int32_t value); uint8_t log2_approx(uint32_t); diff --git a/openair1/SIMULATION/NR_PHY/dlsim.c b/openair1/SIMULATION/NR_PHY/dlsim.c index f7c8752c76..40ad816d2c 100644 --- a/openair1/SIMULATION/NR_PHY/dlsim.c +++ b/openair1/SIMULATION/NR_PHY/dlsim.c @@ -324,7 +324,7 @@ int main(int argc, char **argv) setbuf(stdout, NULL); int c; int i,aa;//,l; - double sigma2, sigma2_dB=10, SNR, snr0=-2.0, snr1=2.0; + double SNR, snr0 = -2.0, snr1 = 2.0; uint8_t snr1set=0; double effRate; //float psnr; @@ -1172,15 +1172,12 @@ int main(int argc, char **argv) } } - int txlev[n_tx]; - int txlev_sum = 0; + // Compute transmitter energy level int l_ofdm = 6; - for (aa=0; aaofdm_symbol_size + (l_ofdm-1)*frame_parms->nb_prefix_samples + frame_parms->nb_prefix_samples0], - frame_parms->ofdm_symbol_size + frame_parms->nb_prefix_samples); - txlev_sum += txlev[aa]; - if (n_trials==1) printf("txlev[%d] = %d (%f dB) txlev_sum %d\n",aa,txlev[aa],10*log10((double)txlev[aa]),txlev_sum); - } + int symbol_offset = slot_offset + l_ofdm * frame_parms->ofdm_symbol_size + (l_ofdm - 1) * frame_parms->nb_prefix_samples + + frame_parms->nb_prefix_samples0; + int symbol_length = frame_parms->ofdm_symbol_size + frame_parms->nb_prefix_samples; + double txlev_sum = compute_tx_energy_level(txdata, n_tx, symbol_offset, symbol_length, n_trials); for (i = 0; i < slot_length; i++) { for (aa=0; aanb_antennas_tx; aa++) { @@ -1189,11 +1186,11 @@ int main(int argc, char **argv) } } - double ts = 1.0/(frame_parms->subcarrier_spacing * frame_parms->ofdm_symbol_size); - //Compute AWGN variance - sigma2_dB = 10 * log10((double)txlev_sum * ((double)UE->frame_parms.ofdm_symbol_size/(12*pdsch_pdu_rel15->rbSize))) - SNR; - sigma2 = pow(10, sigma2_dB/10); - if (n_trials==1) printf("sigma2 %f (%f dB), txlev_sum %f (factor %f)\n",sigma2,sigma2_dB,10*log10((double)txlev_sum),(double)(double)UE->frame_parms.ofdm_symbol_size/(12*pdsch_pdu_rel15->rbSize)); + double ts = 1.0/(frame_parms->subcarrier_spacing * frame_parms->ofdm_symbol_size); + + // Estimate noise power from the transmitter level and SNR + double sigma2 = + compute_noise_variance(txlev_sum, UE->frame_parms.ofdm_symbol_size, pdsch_pdu_rel15->rbSize, 1, SNR, n_trials); for (aa = 0; aa < n_rx; aa++) { bzero(r_re[aa], slot_length * sizeof(double)); diff --git a/openair1/SIMULATION/NR_PHY/prachsim.c b/openair1/SIMULATION/NR_PHY/prachsim.c index f1a419d2a1..4dbac5dd7f 100644 --- a/openair1/SIMULATION/NR_PHY/prachsim.c +++ b/openair1/SIMULATION/NR_PHY/prachsim.c @@ -131,7 +131,7 @@ int main(int argc, char **argv){ sigaction(SIGINT, &sigint_action, &oldaction); get_softmodem_params()->sl_mode = 0; - double sigma2, sigma2_dB = 0, SNR, snr0 = -2.0, snr1 = 0.0, ue_speed0 = 0.0, ue_speed1 = 0.0; + double SNR, snr0 = -2.0, snr1 = 0.0, ue_speed0 = 0.0, ue_speed1 = 0.0; double **s_re, **s_im, **r_re, **r_im, iqim = 0.0, delay_avg = 0, ue_speed = 0, fs=-1, bw; int i, l, aa, aarx, trial, n_frames = 1, rx_prach_start; //, ntrials=1; c16_t **txdata; @@ -728,14 +728,7 @@ int main(int argc, char **argv){ for (trial = 0; trial < n_frames && !stop; trial++) { if (input_fd == NULL) { - sigma2_dB = 10*log10((double)tx_lev) - SNR - 10*log10(N_RB_UL*12/N_ZC); - - if (n_frames==1) - printf("sigma2_dB %f (SNR %f dB) tx_lev_dB %f\n",sigma2_dB,SNR,10*log10((double)tx_lev)); - - //AWGN - sigma2 = pow(10,sigma2_dB/10); - // printf("Sigma2 %f (sigma2_dB %f)\n",sigma2,sigma2_dB); + double sigma2 = compute_noise_variance(tx_lev, N_ZC, N_RB_UL, 1, SNR, n_frames); if (awgn_flag == 0) { multipath_tv_channel(UE2gNB, s_re, s_im, r_re, r_im, frame_parms->samples_per_frame, 0); diff --git a/openair1/SIMULATION/NR_PHY/pucchsim.c b/openair1/SIMULATION/NR_PHY/pucchsim.c index 21d43f48ad..db20b21b8f 100644 --- a/openair1/SIMULATION/NR_PHY/pucchsim.c +++ b/openair1/SIMULATION/NR_PHY/pucchsim.c @@ -96,7 +96,7 @@ int main(int argc, char **argv) sigaction(SIGINT, &sigint_action, &oldaction); int i;//,l; - double sigma2, sigma2_dB=10,SNR,snr0=-2.0,snr1=2.0; + double SNR, snr0 = -2.0, snr1 = 2.0; double cfo=0; uint8_t snr1set=0; double **s_re,**s_im,**r_re,**r_im; @@ -566,15 +566,16 @@ int main(int argc, char **argv) // SNR Computation // standard says: SNR = S / N, where S is the total signal energy, N is the noise energy in the transmission bandwidth (i.e. N_RB_DL resource blocks) // txlev = S. - int txlev = signal_energy((int32_t *)&txdataF[0][startingSymbolIndex*frame_parms->ofdm_symbol_size], frame_parms->ofdm_symbol_size); + + // Compute transmitter energy level + int symbol_offset = startingSymbolIndex * frame_parms->ofdm_symbol_size; + int symbol_length = frame_parms->ofdm_symbol_size; + double txlev = compute_tx_energy_level(txdataF, 1, symbol_offset, symbol_length, n_trials); // sigma2 is variance per dimension, so N/(N_RB*12) // so, sigma2 = N/(N_RB_DL*12) => (S/SNR)/(N_RB*12) int N_RB = (format == 0 || format == 1) ? 1 : nrofPRB; - sigma2_dB = 10*log10(txlev*(N_RB_DL/N_RB))-SNR; - sigma2 = pow(10.0,sigma2_dB/10.0); - - if (n_trials==1) printf("txlev %d (%f dB), offset %d, sigma2 %f ( %f dB)\n",txlev,10*log10(txlev),startingSymbolIndex*frame_parms->ofdm_symbol_size,sigma2,sigma2_dB); + double sigma2 = compute_noise_variance(txlev, N_RB_DL * 12, N_RB, 1, SNR, n_trials); for (int symb=0; symbframe_parms.symbols_per_slot;symb++) { if (symb= startingSymbolIndex+nrofSymbols) { @@ -648,7 +649,16 @@ int main(int argc, char **argv) gNB_I0_measurements(gNB, nr_slot_tx, 0, gNB->frame_parms.symbols_per_slot, rb_mask_ul); start_meas(&gNB->phy_proc_rx); - if (n_trials==1) printf("noise rxlev %d (%d dB), rxlev pucch %d dB sigma2 %f dB, SNR %f, TX %f, I0 (pucch) %d, I0 (avg) %d\n",rxlev,dB_fixed(rxlev),dB_fixed(rxlev_pucch),sigma2_dB,SNR,10*log10((double)txlev*UE->frame_parms.ofdm_symbol_size/12),gNB->measurements.n0_subband_power_tot_dB[startingPRB],gNB->measurements.n0_subband_power_avg_dB); + if (n_trials == 1) + printf("noise rxlev %d (%d dB), rxlev pucch %d dB sigma2 %f dB, SNR %f, TX %f, I0 (pucch) %d, I0 (avg) %d\n", + rxlev, + dB_fixed(rxlev), + dB_fixed(rxlev_pucch), + 10 * log10(sigma2), + SNR, + 10 * log10((double)txlev * UE->frame_parms.ofdm_symbol_size / 12), + gNB->measurements.n0_subband_power_tot_dB[startingPRB], + gNB->measurements.n0_subband_power_avg_dB); if(format==0){ nfapi_nr_uci_pucch_pdu_format_0_1_t uci_pdu; nfapi_nr_pucch_pdu_t pucch_pdu; diff --git a/openair1/SIMULATION/NR_PHY/srssim.c b/openair1/SIMULATION/NR_PHY/srssim.c index fa7388498b..c86ab2b6a9 100644 --- a/openair1/SIMULATION/NR_PHY/srssim.c +++ b/openair1/SIMULATION/NR_PHY/srssim.c @@ -549,7 +549,7 @@ int main(int argc, char *argv[]) int tao_ns_count = 0; for (trial = 0; trial < n_trials && !stop; trial++) { // Estimate noise power from the transmitter level and SNR - double sigma = compute_noise_variance(txlev_sum, ofdm_symbol_size, srs_pdu.bwp_size, SNR, n_trials); + double sigma = compute_noise_variance(txlev_sum, ofdm_symbol_size, srs_pdu.bwp_size, 1, SNR, n_trials); //----------- Apply propagation channel ---------------------------- multipath_channel(UE2gNB, s_re, s_im, r_re, r_im, slot_length, 0, (n_trials == 1) ? 1 : 0); diff --git a/openair1/SIMULATION/NR_PHY/ulsim.c b/openair1/SIMULATION/NR_PHY/ulsim.c index 444492b545..d7bd25555f 100644 --- a/openair1/SIMULATION/NR_PHY/ulsim.c +++ b/openair1/SIMULATION/NR_PHY/ulsim.c @@ -281,7 +281,6 @@ int main(int argc, char *argv[]) char *filename_csv = NULL; int i; double SNR, snr0 = -2.0, snr1 = 2.0; - double sigma, sigma_dB; double snr_step = .2; uint8_t snr1set = 0; int slot = 8, frame = 1; @@ -308,7 +307,7 @@ int main(int argc, char *argv[]) int Imcs = 9; uint8_t precod_nbr_layers = 1; int tx_offset; - int32_t txlev_sum = 0, atxlev[4]; + double txlev_sum = 0; int start_rb = 0; int UE_id = 0; int print_perf = 0; @@ -1401,36 +1400,22 @@ int main(int argc, char *argv[]) } /////////// //////////////////////////////////////////////////// + // Compute transmitter energy level tx_offset = get_samples_slot_timestamp(&gNB->frame_parms, slot); - txlev_sum = 0; - for (int aa = 0; aa < UE->frame_parms.nb_antennas_tx; aa++) { - atxlev[aa] = - signal_energy((int32_t *)&UE->common_vars - .txData[aa][tx_offset + 5 * gNB->frame_parms.ofdm_symbol_size - + 4 * gNB->frame_parms.nb_prefix_samples + gNB->frame_parms.nb_prefix_samples0], - gNB->frame_parms.ofdm_symbol_size + gNB->frame_parms.nb_prefix_samples); - - txlev_sum += atxlev[aa]; - - if (n_trials == 1) - printf("txlev[%d] = %d (%f dB) txlev_sum %d\n", aa, atxlev[aa], 10 * log10((double)atxlev[aa]), txlev_sum); - } + int symbol_offset = tx_offset + 5 * gNB->frame_parms.ofdm_symbol_size + 4 * gNB->frame_parms.nb_prefix_samples + + gNB->frame_parms.nb_prefix_samples0; + int symbol_length = gNB->frame_parms.ofdm_symbol_size + gNB->frame_parms.nb_prefix_samples; + txlev_sum = compute_tx_energy_level(UE->common_vars.txData, + UE->frame_parms.nb_antennas_tx, + symbol_offset, + symbol_length, + n_trials); } else n_trials = 1; if (input_fd == NULL) { - // Justification of division by precod_nbr_layers: - // When the channel is the identity matrix, the results in terms of SNR should be almost equal for 2x2 and 4x4. - sigma_dB = - 10 * log10((double)txlev_sum / precod_nbr_layers * ((double)gNB->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_sum %f (factor %f)\n", - sigma, - sigma_dB, - 10 * log10((double)txlev_sum), - (double)(double)gNB->frame_parms.ofdm_symbol_size / (12 * nb_rb)); + double sigma = + compute_noise_variance(txlev_sum, gNB->frame_parms.ofdm_symbol_size, nb_rb, precod_nbr_layers, SNR, n_trials); for (i = 0; i < slot_length; i++) { for (int aa = 0; aa < UE->frame_parms.nb_antennas_tx; aa++) {