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rewrite nr_srs_channel_estimation() to loop over rx antennas and antenna ports to be able to parallelize

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This commit is contained in:
Rakesh Mundlamuri
2026-01-09 16:58:34 +05:30
parent 1ffb1cfe16
commit a5a09676ad
3 changed files with 132 additions and 120 deletions
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openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c
+78 -92
View File
@@ -769,21 +769,22 @@ void nr_pusch_ptrs_processing(PHY_VARS_gNB *gNB,
} // Antenna loop
}
int nr_srs_channel_estimation(
const PHY_VARS_gNB *gNB,
const int frame,
const int slot,
const nfapi_nr_srs_pdu_t *srs_pdu,
const nr_srs_info_t *nr_srs_info,
const c16_t **srs_generated_signal,
c16_t srs_received_signal[][gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_received_noise[][gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_freq[][1 << srs_pdu->num_ant_ports]
[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_time[][1 << srs_pdu->num_ant_ports][gNB->frame_parms.ofdm_symbol_size],
c16_t srs_estimated_channel_time_shifted[][1 << srs_pdu->num_ant_ports][gNB->frame_parms.ofdm_symbol_size],
int16_t *snr_per_rb,
int8_t *snr)
int nr_srs_channel_estimation(const PHY_VARS_gNB *gNB,
const int frame,
const int slot,
const int ant,
const int p_index,
const nfapi_nr_srs_pdu_t *srs_pdu,
const nr_srs_info_t *nr_srs_info,
const c16_t *srs_generated_signal,
c16_t srs_received_signal[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_received_noise[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_freq[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_time[gNB->frame_parms.ofdm_symbol_size],
c16_t srs_estimated_channel_time_shifted[gNB->frame_parms.ofdm_symbol_size],
uint32_t *signal_power,
uint32_t *noise_power,
int16_t *noise_power_per_rb)
{
#ifdef SRS_DEBUG
LOG_I(NR_PHY, "Calling %s function\n", __FUNCTION__);
@@ -802,7 +803,7 @@ int nr_srs_channel_estimation(
}
c16_t srs_ls_estimated_channel[frame_parms->ofdm_symbol_size * (1 << srs_pdu->num_symbols)];
uint8_t mem_offset = ((16 - ((intptr_t)&srs_estimated_channel_freq[0][0][subcarrier_offset + nr_srs_info->k_0_p[0][0]])) & 0xF)
uint8_t mem_offset = ((16 - ((intptr_t)&srs_estimated_channel_freq[subcarrier_offset + nr_srs_info->k_0_p[p_index][0]])) & 0xF)
>> 2; // >> 2 <=> /sizeof(int32_t)
// filt16_end is {4096,8192,8192,8192,12288,16384,16384,16384,0,0,0,0,0,0,0,0}
@@ -812,8 +813,6 @@ int nr_srs_channel_estimation(
c16_t srs_est[frame_parms->ofdm_symbol_size * (1 << srs_pdu->num_symbols) + mem_offset + 8] __attribute__((aligned(32)));
c16_t ls_estimated = {0};
for (int ant = 0; ant < frame_parms->nb_antennas_rx; ant++) {
for (int p_index = 0; p_index < N_ap; p_index++) {
memset(srs_ls_estimated_channel, 0, frame_parms->ofdm_symbol_size * (1 << srs_pdu->num_symbols) * sizeof(c16_t));
memset(srs_est, 0, (frame_parms->ofdm_symbol_size * (1 << srs_pdu->num_symbols) + mem_offset) * sizeof(c16_t));
@@ -834,8 +833,8 @@ int nr_srs_channel_estimation(
uint16_t subcarrier_cdm = subcarrier;
for (int cdm_idx = 0; cdm_idx < fd_cdm; cdm_idx++) {
c16_t generated_srs = srs_generated_signal[p_index][subcarrier_cdm];
c16_t received_srs = srs_received_signal[ant][subcarrier_cdm];
c16_t generated_srs = srs_generated_signal[subcarrier_cdm];
c16_t received_srs = srs_received_signal[subcarrier_cdm];
// We know that nr_srs_info->srs_generated_signal_bits bits are enough to represent the real and imaginary parts of
// generated_srs. So we only need a nr_srs_info->srs_generated_signal_bits shift to ensure that the result fits into 16
// bits.
@@ -863,10 +862,10 @@ int nr_srs_channel_estimation(
LOG_I(NR_PHY,
"(%4i) %6i\t%6i | %6i\t%6i | %6i\t%6i\n",
subcarrier_log,
srs_generated_signal[p_index][subcarrier].r,
srs_generated_signal[p_index][subcarrier].i,
srs_received_signal[ant][subcarrier].r,
srs_received_signal[ant][subcarrier].i,
srs_generated_signal[subcarrier].r,
srs_generated_signal[subcarrier].i,
srs_received_signal[subcarrier].r,
srs_received_signal[subcarrier].i,
ls_estimated.r,
ls_estimated.i);
#endif
@@ -923,7 +922,7 @@ int nr_srs_channel_estimation(
} // for (int k = 0; k < M_sc_b_SRS; k++)
memcpy(srs_estimated_channel_freq[ant][p_index],
memcpy(srs_estimated_channel_freq,
&srs_est[mem_offset],
(frame_parms->ofdm_symbol_size * (1 << srs_pdu->num_symbols)) * sizeof(c16_t));
@@ -949,10 +948,10 @@ int nr_srs_channel_estimation(
subcarrier_log,
srs_ls_estimated_channel[subcarrier].r,
srs_ls_estimated_channel[subcarrier].i,
srs_estimated_channel_freq[ant][p_index][subcarrier].r,
srs_estimated_channel_freq[ant][p_index][subcarrier].i,
srs_received_noise[ant][subcarrier].r,
srs_received_noise[ant][subcarrier].i);
srs_estimated_channel_freq[subcarrier].r,
srs_estimated_channel_freq[subcarrier].i,
srs_received_noise[subcarrier].r,
srs_received_noise[subcarrier].i);
// Subcarrier increment
subcarrier++;
@@ -963,83 +962,70 @@ int nr_srs_channel_estimation(
#endif
// Convert to time domain
freq2time(gNB->frame_parms.ofdm_symbol_size,
(int16_t *)srs_estimated_channel_freq[ant][p_index],
(int16_t *)srs_estimated_channel_time[ant][p_index]);
freq2time(gNB->frame_parms.ofdm_symbol_size, (int16_t *)srs_estimated_channel_freq, (int16_t *)srs_estimated_channel_time);
memcpy(srs_estimated_channel_time_shifted[ant][p_index],
&srs_estimated_channel_time[ant][p_index][gNB->frame_parms.ofdm_symbol_size >> 1],
memcpy(srs_estimated_channel_time_shifted,
&srs_estimated_channel_time[gNB->frame_parms.ofdm_symbol_size >> 1],
(gNB->frame_parms.ofdm_symbol_size >> 1) * sizeof(c16_t));
memcpy(&srs_estimated_channel_time_shifted[ant][p_index][gNB->frame_parms.ofdm_symbol_size >> 1],
srs_estimated_channel_time[ant][p_index],
memcpy(&srs_estimated_channel_time_shifted[gNB->frame_parms.ofdm_symbol_size >> 1],
srs_estimated_channel_time,
(gNB->frame_parms.ofdm_symbol_size >> 1) * sizeof(c16_t));
} // for (int p_index = 0; p_index < N_ap; p_index++)
} // for (int ant = 0; ant < frame_parms->nb_antennas_rx; ant++)
// Compute wideband SNR
int tot_subcarriers = m_SRS_b * NR_NB_SC_PER_RB;
uint32_t signal_power = 0;
uint32_t noise_power = 0;
for (int ant = 0; ant < frame_parms->nb_antennas_rx; ant++) {
for (int p_index = 0; p_index < N_ap; p_index++) {
uint16_t subcarrier0 = subcarrier_offset + nr_srs_info->k_0_p[p_index][0];
if (subcarrier0 >= frame_parms->ofdm_symbol_size) {
subcarrier0 -= frame_parms->ofdm_symbol_size;
// Compute wideband SNR
int tot_subcarriers = m_SRS_b * NR_NB_SC_PER_RB;
subcarrier = subcarrier_offset + nr_srs_info->k_0_p[p_index][0];
if (subcarrier >= frame_parms->ofdm_symbol_size) {
subcarrier -= frame_parms->ofdm_symbol_size;
}
if (subcarrier0 + tot_subcarriers < frame_parms->ofdm_symbol_size) {
signal_power += signal_energy_nodc(&srs_estimated_channel_freq[ant][p_index][subcarrier0], tot_subcarriers);
if (p_index == 0)
noise_power += signal_energy_nodc(&srs_received_noise[ant][subcarrier0], tot_subcarriers);
} else {
int size1 = frame_parms->ofdm_symbol_size - subcarrier0;
int size2 = tot_subcarriers - size1;
uint64_t signal_power_p1 = signal_energy_nodc(&srs_estimated_channel_freq[ant][p_index][subcarrier0], size1) * size1;
uint64_t signal_power_p2 = signal_energy_nodc(&srs_estimated_channel_freq[ant][p_index][0], size2) * size2;
signal_power += (signal_power_p1 + signal_power_p2) / tot_subcarriers;
if (subcarrier + tot_subcarriers < frame_parms->ofdm_symbol_size) {
*signal_power = signal_energy_nodc(&srs_estimated_channel_freq[subcarrier], tot_subcarriers) / tot_subcarriers;
if (p_index == 0) {
uint64_t noise_power_p1 = signal_energy_nodc(&srs_received_noise[ant][subcarrier0], size1) * size1;
uint64_t noise_power_p2 = signal_energy_nodc(&srs_received_noise[ant][0], size2) * size2;
noise_power += (noise_power_p1 + noise_power_p2) / tot_subcarriers;
*noise_power = signal_energy_nodc(&srs_received_noise[subcarrier], tot_subcarriers) / tot_subcarriers;
}
}
}
}
signal_power = max(signal_power / (frame_parms->nb_antennas_rx * N_ap), 1);
noise_power = max(noise_power / (frame_parms->nb_antennas_rx), 1);
if (signal_power == 0) {
LOG_W(NR_PHY, "Received SRS signal power is 0\n");
return -1;
}
*snr = dB_fixed(signal_power) - dB_fixed(noise_power);
// Compute SNR per RB
uint16_t subcarrier = subcarrier_offset + nr_srs_info->k_0_p[0][0];
for (int rb = 0; rb < m_SRS_b; rb++) {
if (subcarrier >= frame_parms->ofdm_symbol_size) {
subcarrier -= frame_parms->ofdm_symbol_size;
}
uint32_t noise_power_per_rb = 0;
for (int ant = 0; ant < frame_parms->nb_antennas_rx; ant++) {
if (subcarrier + NR_NB_SC_PER_RB < frame_parms->ofdm_symbol_size) {
noise_power_per_rb += signal_energy_nodc(&srs_received_noise[ant][subcarrier], NR_NB_SC_PER_RB);
} else {
int size1 = frame_parms->ofdm_symbol_size - subcarrier;
int size2 = NR_NB_SC_PER_RB - size1;
uint32_t noise_power_per_rb1 = signal_energy_nodc(&srs_received_noise[ant][subcarrier], size1) * size1;
uint32_t noise_power_per_rb2 = signal_energy_nodc(&srs_received_noise[ant][0], size2) * size2;
noise_power_per_rb += (noise_power_per_rb1 + noise_power_per_rb2) / NR_NB_SC_PER_RB;
int size2 = tot_subcarriers - size1;
uint64_t signal_power_p1 = signal_energy_nodc(&srs_estimated_channel_freq[subcarrier], size1) * size1;
uint64_t signal_power_p2 = signal_energy_nodc(&srs_estimated_channel_freq[0], size2) * size2;
*signal_power = (signal_power_p1 + signal_power_p2) / tot_subcarriers;
if (p_index == 0) {
uint64_t noise_power_p1 = signal_energy_nodc(&srs_received_noise[subcarrier], size1) * size1;
uint64_t noise_power_p2 = signal_energy_nodc(&srs_received_noise[0], size2) * size2;
*noise_power = (noise_power_p1 + noise_power_p2) / tot_subcarriers;
}
}
}
noise_power_per_rb = max(noise_power_per_rb / (frame_parms->nb_antennas_rx), 1);
snr_per_rb[rb] = dB_fixed(signal_power) - dB_fixed(noise_power_per_rb);
subcarrier += NR_NB_SC_PER_RB;
*signal_power = max(*signal_power, 1);
if (*signal_power == 0) {
LOG_W(NR_PHY, "Received SRS signal power is 0\n");
return -1;
}
// Compute SNR per RB for port 0
if (p_index == 0) {
subcarrier = subcarrier_offset + nr_srs_info->k_0_p[p_index][0];
for (int rb = 0; rb < m_SRS_b; rb++) {
if (subcarrier >= frame_parms->ofdm_symbol_size) {
subcarrier -= frame_parms->ofdm_symbol_size;
}
if (subcarrier + NR_NB_SC_PER_RB < frame_parms->ofdm_symbol_size) {
noise_power_per_rb[rb] += signal_energy_nodc(&srs_received_noise[subcarrier], NR_NB_SC_PER_RB);
} else {
int size1 = frame_parms->ofdm_symbol_size - subcarrier;
int size2 = NR_NB_SC_PER_RB - size1;
uint32_t noise_power_per_rb1 = signal_energy_nodc(&srs_received_noise[subcarrier], size1) * size1;
uint32_t noise_power_per_rb2 = signal_energy_nodc(&srs_received_noise[0], size2) * size2;
noise_power_per_rb[rb] += (noise_power_per_rb1 + noise_power_per_rb2) / NR_NB_SC_PER_RB;
}
noise_power_per_rb[rb] = max(noise_power_per_rb[rb], 1);
subcarrier += NR_NB_SC_PER_RB;
#ifdef SRS_DEBUG
LOG_I(NR_PHY, "[RB %3i] noise_power_per_rb = %i, snr_per_rb = %i dB\n", rb, noise_power_per_rb, snr_per_rb[rb]);
LOG_I(NR_PHY, "[RB %3i] noise_power_per_rb = %i, snr_per_rb = %i dB\n", rb, noise_power_per_rb, snr_per_rb[rb]);
#endif
}
}
}
#ifdef SRS_DEBUG
LOG_I(NR_PHY, "signal_power = %i dB, noise_power = %i dB, SNR = %i dB\n", dB_fixed(signal_power), dB_fixed(noise_power), *snr);
openair1/PHY/NR_ESTIMATION/nr_ul_estimation.h
+16 -15
View File
@@ -70,21 +70,22 @@ void nr_pusch_ptrs_processing(PHY_VARS_gNB *gNB,
unsigned char symbol,
uint32_t nb_re_pusch);
int nr_srs_channel_estimation(
const PHY_VARS_gNB *gNB,
const int frame,
const int slot,
const nfapi_nr_srs_pdu_t *srs_pdu,
const nr_srs_info_t *nr_srs_info,
const c16_t **srs_generated_signal,
c16_t srs_received_signal[][gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_received_noise[][gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_freq[][1 << srs_pdu->num_ant_ports]
[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_time[][1 << srs_pdu->num_ant_ports][gNB->frame_parms.ofdm_symbol_size],
c16_t srs_estimated_channel_time_shifted[][1 << srs_pdu->num_ant_ports][gNB->frame_parms.ofdm_symbol_size],
int16_t *snr_per_rb,
int8_t *snr);
int nr_srs_channel_estimation(const PHY_VARS_gNB *gNB,
const int frame,
const int slot,
const int ant,
const int p_index,
const nfapi_nr_srs_pdu_t *srs_pdu,
const nr_srs_info_t *nr_srs_info,
const c16_t *srs_generated_signal,
c16_t srs_received_signal[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_received_noise[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_freq[gNB->frame_parms.ofdm_symbol_size * (1 << srs_pdu->num_symbols)],
c16_t srs_estimated_channel_time[gNB->frame_parms.ofdm_symbol_size],
c16_t srs_estimated_channel_time_shifted[gNB->frame_parms.ofdm_symbol_size],
uint32_t *signal_power,
uint32_t *noise_power,
int16_t *noise_power_per_rb);
void nr_freq_equalization(NR_DL_FRAME_PARMS *frame_parms,
c16_t *rxdataF_comp,
openair1/SCHED_NR/phy_procedures_nr_gNB.c
+38 -13
View File
@@ -889,21 +889,46 @@ void nr_srs_rx_procedures(PHY_VARS_gNB *gNB,
*srs_est = nr_get_srs_signal(gNB, rxdataF, frame_rx, slot_rx, srs_pdu, nr_srs_info, srs_received_signal, srs_received_noise);
stop_meas(&gNB->get_srs_signal_stats);
uint32_t signal_power_avg = 0;
uint32_t noise_power_avg = 0;
int16_t noise_power_per_rb[srs_pdu->bwp_size];
memset(noise_power_per_rb, 0, srs_pdu->bwp_size * sizeof(int16_t));
if (*srs_est >= 0) {
start_meas(&gNB->srs_channel_estimation_stats);
nr_srs_channel_estimation(gNB,
frame_rx,
slot_rx,
srs_pdu,
nr_srs_info,
(const c16_t **)nr_srs_info->srs_generated_signal,
srs_received_signal,
srs_received_noise,
srs_estimated_channel_freq,
srs_estimated_channel_time,
srs_estimated_channel_time_shifted,
snr_per_rb,
&gNB->srs->snr);
for (int ant_rx_ind = 0; ant_rx_ind < nb_antennas_rx; ant_rx_ind++) {
uint32_t noise_power = 0;
for (int p_ind = 0; p_ind < N_ap; p_ind++) {
uint32_t signal_power = 0;
nr_srs_channel_estimation(gNB,
frame_rx,
slot_rx,
ant_rx_ind,
p_ind,
srs_pdu,
nr_srs_info,
nr_srs_info->srs_generated_signal[p_ind],
srs_received_signal[ant_rx_ind],
srs_received_noise[ant_rx_ind],
srs_estimated_channel_freq[ant_rx_ind][p_ind],
srs_estimated_channel_time[ant_rx_ind][p_ind],
srs_estimated_channel_time_shifted[ant_rx_ind][p_ind],
&signal_power,
&noise_power,
noise_power_per_rb);
signal_power_avg += signal_power;
}
noise_power_avg += noise_power;
}
signal_power_avg /= (nb_antennas_rx * N_ap);
noise_power_avg /= nb_antennas_rx;
signal_power_avg = max(signal_power_avg, 1);
gNB->srs->snr = dB_fixed(signal_power_avg) - dB_fixed(max(noise_power_avg, 1));
const uint16_t m_SRS_b = get_m_srs(srs_pdu->config_index, srs_pdu->bandwidth_index);
for (int rb = 0; rb < m_SRS_b; rb++) {
snr_per_rb[rb] = dB_fixed(signal_power_avg) - dB_fixed(max(noise_power_per_rb[rb] / nb_antennas_rx, 1));
}
stop_meas(&gNB->srs_channel_estimation_stats);
}