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Commit 386881c3 authored by Sagar Parsawar's avatar Sagar Parsawar Committed by francescomani
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Fixed PRS IDFT 16x oversampling buffer issue

parent 970e65a4
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Showing with 55 additions and 37 deletions
openair1/PHY/NR_UE_ESTIMATION/nr_dl_channel_estimation.c
View file @ 386881c3
......@@ -97,8 +97,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
int16_t *rxF, *pil, mod_prs[NR_MAX_PRS_LENGTH << 1];
const int16_t *fl, *fm, *fmm, *fml, *fmr, *fr;
int16_t ch[2] = {0};
int16_t k_prime = 0, k = 0, re_offset = 0, first_half = 0, second_half = 0;
int32_t ch_pwr = 0, snr = 0, noiseFig[2] = {0}, mean_val = 0;
int16_t k_prime = 0, k = 0;
int32_t ch_pwr = 0, snr = 0, noiseFig[2] = {0}, rsrp = 0, mean_val = 0, prs_toa = 0;
double ch_pwr_dbm = 0.0f;
#ifdef DEBUG_PRS_CHEST
char filename[64] = {0}, varname[64] = {0};
......@@ -106,7 +106,10 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
int16_t *ch_tmp = (int16_t *)ch_tmp_buf;
int16_t scale_factor = (1.0f/(float)(prs_cfg->NumPRSSymbols))*(1<<15);
int16_t num_pilots = (12/prs_cfg->CombSize)*prs_cfg->NumRB;
int16_t start_offset = (NR_PRS_IDFT_OVERSAMP_FACTOR-1)*frame_params->ofdm_symbol_size>>1;
int16_t first_half = frame_params->ofdm_symbol_size - frame_params->first_carrier_offset;
int16_t second_half = (prs_cfg->NumRB*12) - first_half;
int16_t start_offset = NR_PRS_IDFT_OVERSAMP_FACTOR*frame_params->ofdm_symbol_size - first_half;
LOG_D(PHY, "start_offset %d, first_half %d, second_half %d\n", start_offset, first_half, second_half);
int16_t k_prime_table[K_PRIME_TABLE_ROW_SIZE][K_PRIME_TABLE_COL_SIZE] = PRS_K_PRIME_TABLE;
for(int l = prs_cfg->SymbolStart; l < prs_cfg->SymbolStart+prs_cfg->NumPRSSymbols; l++)
......@@ -138,10 +141,11 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
for (rxAnt=0; rxAnt < frame_params->nb_antennas_rx; rxAnt++)
{
snr = 0;
// reset variables
snr = 0; rsrp = 0;
// calculate RE offset
k = re_offset = (prs_cfg->REOffset+k_prime) % prs_cfg->CombSize + prs_cfg->RBOffset*12 + frame_params->first_carrier_offset;
k = (prs_cfg->REOffset+k_prime) % prs_cfg->CombSize + prs_cfg->RBOffset*12 + frame_params->first_carrier_offset;
// Channel estimation and interpolation
pil = (int16_t *)&mod_prs[0];
......@@ -183,7 +187,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
8);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*(c16_t*)rxF) - squaredMod(*(c16_t*)noiseFig)) - 10*log10(squaredMod(*(c16_t*)noiseFig));
......@@ -214,7 +219,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
8);
}
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*(c16_t*)rxF) - squaredMod(*(c16_t*)noiseFig)) - 10*log10(squaredMod(*(c16_t*)noiseFig));
......@@ -242,7 +248,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
8);
}
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
......@@ -263,16 +270,14 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
8);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d, SNR %+2d dB: rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, num_pilots-1, snr/num_pilots, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
// average out the SNR computed
snr = snr/num_pilots;
prs_meas[rxAnt]->snr = snr;
}
else if(prs_cfg->CombSize == 4)
{
......@@ -328,7 +333,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
16);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
......@@ -346,7 +352,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
16);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
......@@ -368,7 +375,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
16);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
......@@ -389,7 +397,8 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
16);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
......@@ -407,22 +416,24 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
ch_tmp,
16);
//SNR estimation
//SNR & RSRP estimation
rsrp += squaredMod(*((c16_t*)rxF);
noiseFig[0] = rxF[0] - (int16_t)(((int32_t)ch[0]*pil[0] - (int32_t)ch[1]*pil[1])>>15);
noiseFig[1] = rxF[1] - (int16_t)(((int32_t)ch[1]*pil[0] + (int32_t)ch[0]*pil[1])>>15);
snr += 10*log10(squaredMod(*((c16_t*)rxF)) - squaredMod(*((c16_t*)noiseFig))) - 10*log10(squaredMod(*((c16_t*)noiseFig)));
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d, SNR %+2d dB: rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, +%d) \n", rxAnt, num_pilots-1, snr/num_pilots, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
// average out the SNR computed
snr = snr/num_pilots;
prs_meas[rxAnt]->snr = snr;
}
else
{
AssertFatal((prs_cfg->CombSize == 2)||(prs_cfg->CombSize == 4), "[%s] DL PRS CombSize other than 2 and 4 are NOT supported currently. Exiting!!!", __FUNCTION__);
}
// average out the SNR and RSRP computed
prs_meas[rxAnt]->snr = snr/(float)num_pilots;
prs_meas[rxAnt]->rsrp = rsrp/(float)num_pilots;
//reset channel pointer
ch_tmp = (int16_t*)ch_tmp_buf;
} // for rxAnt
......@@ -451,12 +462,10 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
#endif
// Place PRS channel estimates in FFT shifted format
first_half = frame_params->ofdm_symbol_size - re_offset;
second_half = (prs_cfg->NumRB*12) - first_half;
if(first_half > 0)
memcpy((int16_t *)&chF_interpol[rxAnt][start_offset+re_offset], &ch_tmp[0], first_half*sizeof(int32_t));
memcpy((int16_t *)&chF_interpol[rxAnt][start_offset], &ch_tmp[0], first_half*sizeof(int32_t));
if(second_half > 0)
memcpy((int16_t *)&chF_interpol[rxAnt][start_offset], &ch_tmp[(first_half<<1)], second_half*sizeof(int32_t));
memcpy((int16_t *)&chF_interpol[rxAnt][0], &ch_tmp[first_half<<1], second_half*sizeof(int32_t));
// Time domain IMPULSE response
idft_size_idx_t idftsizeidx;
......@@ -541,9 +550,9 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
// peak estimator
mean_val = abs32((int32_t)ch_tmp[(prs_cfg->NumRB*12)]);
peak_estimator(&chT_interpol[rxAnt][start_offset],
frame_params->ofdm_symbol_size,
&prs_meas[rxAnt]->dl_toa,
peak_estimator(&chT_interpol[rxAnt][0],
NR_PRS_IDFT_OVERSAMP_FACTOR*frame_params->ofdm_symbol_size,
&prs_toa,
&ch_pwr,
mean_val);
......@@ -552,13 +561,20 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
- 10*log10(pow(2,30)) - ((int)openair0_cfg[0].rx_gain[0]
- (int)openair0_cfg[0].rx_gain_offset[0]) - dB_fixed(frame_params->ofdm_symbol_size);
prs_meas[rxAnt]->rsrp_dBm = 10*log10(prs_meas[rxAnt]->rsrp) + 30
- 10*log10(pow(2,30)) - ((int)openair0_cfg[0].rx_gain[0]
- (int)openair0_cfg[0].rx_gain_offset[0]) - dB_fixed(ue->frame_parms.ofdm_symbol_size);
//prs measurements
prs_meas[rxAnt]->gNB_id = gNB_id;
prs_meas[rxAnt]->sfn = proc->frame_rx;
prs_meas[rxAnt]->slot = proc->nr_slot_rx;
prs_meas[rxAnt]->rxAnt_idx = rxAnt;
prs_meas[rxAnt]->dl_aoa = rsc_id;
LOG_I(PHY, "[gNB %d][rsc %d][Rx %d][sfn %d][slot %d] DL PRS ToA ==> %d / %d samples, peak channel power %.1f dBm, SNR %+2d dB\n", gNB_id, rsc_id, rxAnt, proc->frame_rx, proc->nr_slot_rx, prs_meas[rxAnt]->dl_toa, frame_params->ofdm_symbol_size, ch_pwr_dbm, prs_meas[rxAnt]->snr);
prs_meas[rxAnt]->dl_toa = prs_toa/(float)NR_PRS_IDFT_OVERSAMP_FACTOR;
if ((frame_params->ofdm_symbol_size - prs_meas[rxAnt]->dl_toa) < frame_params->ofdm_symbol_size/2)
prs_meas[rxAnt]->dl_toa -= (frame_params->ofdm_symbol_size);
LOG_I(PHY, "[gNB %d][rsc %d][Rx %d][sfn %d][slot %d] DL PRS ToA ==> %.1f / %d samples, peak channel power %.1f dBm, SNR %+.1f dB, rsrp %+.1f dBm\n", gNB_id, rsc_id, rxAnt, proc->frame_rx, proc->nr_slot_rx, prs_meas[rxAnt]->dl_toa, frame_params->ofdm_symbol_size, ch_pwr_dbm, prs_meas[rxAnt]->snr, prs_meas[rxAnt]->rsrp_dBm);
#ifdef DEBUG_PRS_CHEST
sprintf(filename, "%s%i%s", "PRSpilot_", rxAnt, ".m");
......@@ -581,11 +597,11 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
T(T_UE_PHY_DL_CHANNEL_ESTIMATE_FREQ, T_INT(gNB_id), T_INT(rsc_id),
T_INT(proc->frame_rx), T_INT(proc->nr_slot_rx),
T_INT(rxAnt), T_BUFFER(&chF_interpol[rxAnt][start_offset], frame_params->ofdm_symbol_size*sizeof(int32_t)));
T_INT(rxAnt), T_BUFFER(&chF_interpol[rxAnt][0], NR_PRS_IDFT_OVERSAMP_FACTOR*frame_params->ofdm_symbol_size*sizeof(int32_t)));
T(T_UE_PHY_DL_CHANNEL_ESTIMATE, T_INT(gNB_id), T_INT(rsc_id),
T_INT(proc->frame_rx), T_INT(proc->nr_slot_rx),
T_INT(rxAnt), T_BUFFER(&chT_interpol[rxAnt][start_offset], frame_params->ofdm_symbol_size*sizeof(int32_t)));
T_INT(rxAnt), T_BUFFER(&chT_interpol[rxAnt][0], NR_PRS_IDFT_OVERSAMP_FACTOR*frame_params->ofdm_symbol_size*sizeof(int32_t)));
}
return(0);
......
openair1/PHY/defs_nr_common.h
View file @ 386881c3
......@@ -289,9 +289,11 @@ typedef struct {
int32_t sfn;
int8_t slot;
int8_t rxAnt_idx;
int32_t dl_toa;
float dl_toa;
int32_t dl_aoa;
int32_t snr;
float snr;
float rsrp;
float rsrp_dBm;
int32_t reserved;
} prs_meas_t;
......
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