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OAI UE: Added SNR measurements and averaging PRS channel estimates over NumPRSSymbols

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This commit is contained in:
Sagar Parsawar
2022-04-05 15:02:47 +02:00
parent a907d3d220
commit f5587fcdca
1 changed files with 221 additions and 164 deletions
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openair1/PHY/NR_UE_ESTIMATION/nr_dl_channel_estimation.c
+150 -93
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@@ -38,19 +38,22 @@
//#define DEBUG_PRS_CHEST //#define DEBUG_PRS_CHEST
//#define DEBUG_PRS_PRINTS //#define DEBUG_PRS_PRINTS
extern short nr_qpsk_mod_table[8]; extern short nr_qpsk_mod_table[8];
int nr_prs_channel_estimation(uint8_t gNB_id,
PHY_VARS_NR_UE *ue,
UE_nr_rxtx_proc_t *proc,
NR_DL_FRAME_PARMS *frame_params)
{
// Get K_Prime from the table for the length of PRS or LPRS
int k_prime_table[4][12] = { int k_prime_table[4][12] = {
{0,1,0,1,0,1,0,1,0,1,0,1}, {0,1,0,1,0,1,0,1,0,1,0,1},
{0,2,1,3,0,2,1,3,0,2,1,3}, {0,2,1,3,0,2,1,3,0,2,1,3},
{0,3,1,4,2,5,0,3,1,4,2,5}, {0,3,1,4,2,5,0,3,1,4,2,5},
{0,6,3,9,1,7,4,10,2,8,5,11}}; {0,6,3,9,1,7,4,10,2,8,5,11}};
static inline int abs32(int x)
{
return (((int)((short*)&x)[0])*((int)((short*)&x)[0]) + ((int)((short*)&x)[1])*((int)((short*)&x)[1]));
}
int nr_prs_channel_estimation(uint8_t gNB_id,
PHY_VARS_NR_UE *ue,
UE_nr_rxtx_proc_t *proc,
NR_DL_FRAME_PARMS *frame_params)
{
int32_t **rxdataF = ue->common_vars.common_vars_rx_data_per_thread[proc->thread_id].rxdataF; int32_t **rxdataF = ue->common_vars.common_vars_rx_data_per_thread[proc->thread_id].rxdataF;
uint32_t **nr_gold_prs = ue->nr_gold_prs[proc->nr_slot_rx]; uint32_t **nr_gold_prs = ue->nr_gold_prs[proc->nr_slot_rx];
prs_data_t *prs_cfg = &ue->prs_vars[gNB_id]->prs_cfg; prs_data_t *prs_cfg = &ue->prs_vars[gNB_id]->prs_cfg;
@@ -59,16 +62,18 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
int32_t **prs_chestT = ue->prs_vars[gNB_id]->prs_ch_estimates_time; int32_t **prs_chestT = ue->prs_vars[gNB_id]->prs_ch_estimates_time;
uint8_t rxAnt = 0, idx = prs_cfg->NPRSID; uint8_t rxAnt = 0, idx = prs_cfg->NPRSID;
int16_t ch[2] = {0}, *rxF, *pil, *fl,*fm, *fmm, *fml, *fmr, *fr, mod_prs[NR_MAX_PRS_LENGTH<<1]; int16_t *rxF, *pil, *fl, *fm, *fmm, *fml, *fmr, *fr, mod_prs[NR_MAX_PRS_LENGTH<<1];
int16_t k_prime = 0, k = 0, re_offset = 0, second_half = 0; int16_t ch[2] = {0}, noiseFig[2] = {0};
int16_t *ch_freq = (int16_t *)malloc16_clear(frame_params->ofdm_symbol_size*sizeof(int32_t)); int16_t k_prime = 0, k = 0, re_offset = 0, first_half = 0, second_half = 0;
int32_t *ch_time = (int32_t *)malloc16_clear(frame_params->ofdm_symbol_size*sizeof(int32_t)); int16_t *ch_tmp = (int16_t *)malloc16_clear(frame_params->ofdm_symbol_size*sizeof(int32_t));
AssertFatal(((ch_freq != NULL) || (ch_time != NULL)), "nr_prs_channel_estimation: channel estimate buffer initialization failed!!"); AssertFatal((ch_tmp != NULL), "[%s] channel estimate buffer initialization failed!!", __FUNCTION__);
int16_t *ch_init = ch_freq; int32_t ch_pwr = 0, snr = 0;
int32_t ch_pwr= 0;
#ifdef DEBUG_PRS_CHEST #ifdef DEBUG_PRS_CHEST
char filename[128] = {0}, varname[128] = {0}; char filename[64] = {0}, varname[64] = {0};
#endif #endif
int16_t *ch_init = ch_tmp;
int16_t scale_factor = (1.0f/(float)(prs_cfg->NumPRSSymbols))*(1<<15);
int16_t num_pilots = (12/prs_cfg->CombSize)*prs_cfg->NumRB;
for(int l = prs_cfg->SymbolStart; l < prs_cfg->SymbolStart+prs_cfg->NumPRSSymbols; l++) for(int l = prs_cfg->SymbolStart; l < prs_cfg->SymbolStart+prs_cfg->NumPRSSymbols; l++)
{ {
@@ -90,7 +95,7 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
printf("[gNB %d] PRS config l %d k_prime %d:\nprs_cfg->SymbolStart %d\nprs_cfg->NumPRSSymbols %d\nprs_cfg->NumRB %d\nprs_cfg->CombSize %d\n", gNB_id, l, k_prime, prs_cfg->SymbolStart, prs_cfg->NumPRSSymbols, prs_cfg->NumRB, prs_cfg->CombSize); printf("[gNB %d] PRS config l %d k_prime %d:\nprs_cfg->SymbolStart %d\nprs_cfg->NumPRSSymbols %d\nprs_cfg->NumRB %d\nprs_cfg->CombSize %d\n", gNB_id, l, k_prime, prs_cfg->SymbolStart, prs_cfg->NumPRSSymbols, prs_cfg->NumRB, prs_cfg->CombSize);
#endif #endif
// Pilots generation and modulation // Pilots generation and modulation
for (int m = 0; m < (12/prs_cfg->CombSize)*prs_cfg->NumRB; m++) for (int m = 0; m < num_pilots; m++)
{ {
idx = (((nr_gold_prs[l][(m<<1)>>5])>>((m<<1)&0x1f))&3); idx = (((nr_gold_prs[l][(m<<1)>>5])>>((m<<1)&0x1f))&3);
mod_prs[m<<1] = nr_qpsk_mod_table[idx<<1]; mod_prs[m<<1] = nr_qpsk_mod_table[idx<<1];
@@ -99,13 +104,15 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
for (rxAnt=0; rxAnt < frame_params->nb_antennas_rx; rxAnt++) for (rxAnt=0; rxAnt < frame_params->nb_antennas_rx; rxAnt++)
{ {
snr = 0;
// calculate RE offset // calculate RE offset
k = re_offset = (prs_cfg->REOffset+k_prime) % prs_cfg->CombSize + prs_cfg->RBOffset*12 + frame_params->first_carrier_offset; k = re_offset = (prs_cfg->REOffset+k_prime) % prs_cfg->CombSize + prs_cfg->RBOffset*12 + frame_params->first_carrier_offset;
// Channel estimation and interpolation // Channel estimation and interpolation
pil = (int16_t *)&mod_prs[0]; pil = (int16_t *)&mod_prs[0];
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
memset(ch_freq,0,sizeof(int32_t)*(ue->frame_parms.ofdm_symbol_size)); //memset(ch_tmp,0,sizeof(int32_t)*(ue->frame_parms.ofdm_symbol_size));
if(prs_cfg->CombSize == 2) if(prs_cfg->CombSize == 2)
{ {
@@ -138,80 +145,101 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
//Start pilot //Start pilot
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, 0, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fl, multadd_real_vector_complex_scalar(fl,
ch, ch,
ch_freq, ch_tmp,
8); 8);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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, 0, snr, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
//Middle pilots //Middle pilots
for(int pIdx = 1; pIdx < prs_cfg->NumRB*(12/prs_cfg->CombSize)-1; pIdx+=2) for(int pIdx = 1; pIdx < num_pilots-1; pIdx+=2)
{ {
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, pIdx, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
if(pIdx == 1) // 2nd pilot if(pIdx == 1) // 2nd pilot
{ {
multadd_real_vector_complex_scalar(fml, multadd_real_vector_complex_scalar(fml,
ch, ch,
ch_freq, ch_tmp,
8); 8);
} }
else else
{ {
multadd_real_vector_complex_scalar(fm, multadd_real_vector_complex_scalar(fm,
ch, ch,
ch_freq, ch_tmp,
8); 8);
} }
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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, pIdx, snr/(pIdx+1), rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS if(pIdx == (num_pilots-3)) // 2nd last pilot
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, pIdx+1, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
if(pIdx == (prs_cfg->NumRB*(12/prs_cfg->CombSize)-3)) // 2nd last pilot
{ {
multadd_real_vector_complex_scalar(fmr, multadd_real_vector_complex_scalar(fmr,
ch, ch,
ch_freq, ch_tmp,
8); 8);
} }
else else
{ {
multadd_real_vector_complex_scalar(fmm, multadd_real_vector_complex_scalar(fmm,
ch, ch,
ch_freq, ch_tmp,
8); 8);
} }
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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, pIdx+1, snr/(pIdx+2), rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
ch_freq +=8; ch_tmp +=8;
} }
//End pilot //End pilot
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, prs_cfg->NumRB*(12/prs_cfg->CombSize)-1, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fr, multadd_real_vector_complex_scalar(fr,
ch, ch,
ch_freq, ch_tmp,
8); 8);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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][l].snr = snr;
} }
else if(prs_cfg->CombSize == 4) else if(prs_cfg->CombSize == 4)
{ {
@@ -262,103 +290,144 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
//Start pilot //Start pilot
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, 0, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fl, multadd_real_vector_complex_scalar(fl,
ch, ch,
ch_freq, ch_tmp,
16); 16);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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, 0, snr, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, 1, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fml, multadd_real_vector_complex_scalar(fml,
ch, ch,
ch_freq, ch_tmp,
16); 16);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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, 1, snr/2, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
ch_freq +=8; ch_tmp +=8;
//Middle pilots //Middle pilots
for(int pIdx = 2; pIdx < prs_cfg->NumRB*(12/prs_cfg->CombSize)-2; pIdx++) for(int pIdx = 2; pIdx < num_pilots-2; pIdx++)
{ {
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, pIdx, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fmm, multadd_real_vector_complex_scalar(fmm,
ch, ch,
ch_freq, ch_tmp,
16); 16);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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, pIdx, snr/(pIdx+1), rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
ch_freq +=8; ch_tmp +=8;
} }
//End pilot //End pilot
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, %+d) \n", rxAnt, prs_cfg->NumRB*(12/prs_cfg->CombSize)-2, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fmr, multadd_real_vector_complex_scalar(fmr,
ch, ch,
ch_freq, ch_tmp,
16); 16);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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-2, snr/(num_pilots-1), rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
pil +=2; pil +=2;
k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size; k = (k+prs_cfg->CombSize) % frame_params->ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k]; rxF = (int16_t *)&rxdataF[rxAnt][l*frame_params->ofdm_symbol_size + k];
ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15); ch[0] = (int16_t)(((int32_t)rxF[0]*pil[0] + (int32_t)rxF[1]*pil[1])>>15);
ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15); ch[1] = (int16_t)(((int32_t)rxF[1]*pil[0] - (int32_t)rxF[0]*pil[1])>>15);
#ifdef DEBUG_PRS_PRINTS
printf("[Rx %d] pilot %3d : rxF - > (%+3d, %+3d) addr %p ch -> (%+3d, %+3d), pil -> (%+d, +%d) \n", rxAnt, prs_cfg->NumRB*(12/prs_cfg->CombSize)-1, rxF[0],rxF[1],&rxF[0],ch[0],ch[1],pil[0],pil[1]);
#endif
multadd_real_vector_complex_scalar(fr, multadd_real_vector_complex_scalar(fr,
ch, ch,
ch_freq, ch_tmp,
16); 16);
//SNR estimation
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(abs32(*((int*)rxF)) - abs32(*((int*)noiseFig))) - 10*log10(abs32(*((int*)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][l].snr = snr;
} }
else else
{ {
AssertFatal((prs_cfg->CombSize == 2)||(prs_cfg->CombSize == 4), "[NR_PRS Channel EStimation] CombSize other than 2 and 4 are NOT supported currently. Exiting!!!"); AssertFatal((prs_cfg->CombSize == 2)||(prs_cfg->CombSize == 4), "[%s] DL PRS CombSize other than 2 and 4 are NOT supported currently. Exiting!!!", __FUNCTION__);
} }
//reset channel pointer //reset channel pointer
ch_freq = ch_init; ch_tmp = ch_init;
} // for rxAnt
} //for l
int16_t l = 0; //symbIdx
for (rxAnt=0; rxAnt < frame_params->nb_antennas_rx; rxAnt++)
{
// scale by averaging factor 1/NumPrsSymbols
multadd_complex_vector_real_scalar(ch_tmp,
scale_factor,
ch_tmp,
1,
frame_params->ofdm_symbol_size);
#ifdef DEBUG_PRS_PRINTS #ifdef DEBUG_PRS_PRINTS
for (int rb = 0; rb < prs_cfg->NumRB; rb++) for (int rb = 0; rb < prs_cfg->NumRB; rb++)
{ {
printf("================================================================\n"); printf("================================================================\n");
printf("\t\t[gNB %d][Rx %d][PRS symb %d, RB %d]\n", gNB_id, rxAnt, l, rb); printf("\t\t\t[gNB %d][Rx %d][RB %d]\n", gNB_id, rxAnt, rb);
printf("================================================================\n"); printf("================================================================\n");
idx = (12*rb)<<1; idx = (12*rb)<<1;
printf("%4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d\n", ch_freq[idx], ch_freq[idx+1], ch_freq[idx+2], ch_freq[idx+3], ch_freq[idx+4], ch_freq[idx+5], ch_freq[idx+6], ch_freq[idx+7], ch_freq[idx+8], ch_freq[idx+9], ch_freq[idx+10], ch_freq[idx+11]); printf("%4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d\n", ch_tmp[idx], ch_tmp[idx+1], ch_tmp[idx+2], ch_tmp[idx+3], ch_tmp[idx+4], ch_tmp[idx+5], ch_tmp[idx+6], ch_tmp[idx+7], ch_tmp[idx+8], ch_tmp[idx+9], ch_tmp[idx+10], ch_tmp[idx+11]);
printf("%4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d\n", ch_freq[idx+12], ch_freq[idx+13], ch_freq[idx+14], ch_freq[idx+15], ch_freq[idx+16], ch_freq[idx+17], ch_freq[idx+18], ch_freq[idx+19], ch_freq[idx+20], ch_freq[idx+21], ch_freq[idx+22], ch_freq[idx+23]); printf("%4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d %4d\n", ch_tmp[idx+12], ch_tmp[idx+13], ch_tmp[idx+14], ch_tmp[idx+15], ch_tmp[idx+16], ch_tmp[idx+17], ch_tmp[idx+18], ch_tmp[idx+19], ch_tmp[idx+20], ch_tmp[idx+21], ch_tmp[idx+22], ch_tmp[idx+23]);
printf("\n"); printf("\n");
} }
#endif #endif
// Place PRS channel estimates in rxdataF shifted format
second_half = (prs_cfg->NumRB*12-(frame_params->ofdm_symbol_size-re_offset)); // Place PRS channel estimates in FFT shifted format
memcpy((int16_t *)&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size+re_offset], &ch_init[0], (frame_params->ofdm_symbol_size - re_offset)*sizeof(int32_t)); first_half = frame_params->ofdm_symbol_size - re_offset;
second_half = (prs_cfg->NumRB*12) - first_half;
if(first_half > 0)
memcpy((int16_t *)&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size+re_offset], &ch_tmp[0], first_half*sizeof(int32_t));
if(second_half > 0) if(second_half > 0)
memcpy((int16_t *)&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size], &ch_init[(frame_params->ofdm_symbol_size - re_offset)<<1], second_half*sizeof(int32_t)); memcpy((int16_t *)&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size], &ch_tmp[(frame_params->ofdm_symbol_size - re_offset)<<1], second_half*sizeof(int32_t));
// Time domain IMPULSE response // Time domain IMPULSE response
idft_size_idx_t idftsizeidx; idft_size_idx_t idftsizeidx;
switch (frame_params->ofdm_symbol_size) { switch (frame_params->ofdm_symbol_size) {
case 128: case 128:
idftsizeidx = IDFT_128; idftsizeidx = IDFT_128;
@@ -403,11 +472,11 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
idft(idftsizeidx, idft(idftsizeidx,
(int16_t *)&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size], (int16_t *)&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size],
(int16_t *)&ch_time[0],1); (int16_t *)&ch_tmp[0],1);
// rearrange impulse response // rearrange impulse response
memcpy((int16_t *)&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size], &ch_time[frame_params->ofdm_symbol_size>>1], (frame_params->ofdm_symbol_size>>1)*sizeof(int32_t)); memcpy((int16_t *)&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size], &ch_tmp[frame_params->ofdm_symbol_size], (frame_params->ofdm_symbol_size>>1)*sizeof(int32_t));
memcpy((int16_t *)&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size + (frame_params->ofdm_symbol_size>>1)], &ch_time[0], (frame_params->ofdm_symbol_size>>1)*sizeof(int32_t)); memcpy((int16_t *)&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size + (frame_params->ofdm_symbol_size>>1)], &ch_tmp[0], (frame_params->ofdm_symbol_size>>1)*sizeof(int32_t));
// peak estimator // peak estimator
peak_estimator(&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size], peak_estimator(&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size],
@@ -417,19 +486,13 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
LOG_I(PHY, "[gNB %d][Rx %d][sfn %d][slot %d] ToA for PRS symbol %2d ==> %d / %d samples, peak channel power %.1f dB\n", gNB_id, rxAnt, proc->frame_rx, proc->nr_slot_rx, l, prs_meas[rxAnt][l].dl_toa-(frame_params->ofdm_symbol_size>>1), frame_params->ofdm_symbol_size, 10*log10(ch_pwr)); LOG_I(PHY, "[gNB %d][Rx %d][sfn %d][slot %d] ToA for PRS symbol %2d ==> %d / %d samples, peak channel power %.1f dB\n", gNB_id, rxAnt, proc->frame_rx, proc->nr_slot_rx, l, prs_meas[rxAnt][l].dl_toa-(frame_params->ofdm_symbol_size>>1), frame_params->ofdm_symbol_size, 10*log10(ch_pwr));
//prs measurements //prs measurements
prs_meas[rxAnt][l].gNB_id = 0; prs_meas[rxAnt][l].gNB_id = gNB_id;
prs_meas[rxAnt][l].timestamp = 0; prs_meas[rxAnt][l].timestamp = 0; //TODO
prs_meas[rxAnt][l].sfn = proc->frame_rx; prs_meas[rxAnt][l].sfn = proc->frame_rx;
prs_meas[rxAnt][l].slot = proc->nr_slot_rx; prs_meas[rxAnt][l].slot = proc->nr_slot_rx;
prs_meas[rxAnt][l].symbol = l;
prs_meas[rxAnt][l].rxAnt_idx = rxAnt; prs_meas[rxAnt][l].rxAnt_idx = rxAnt;
prs_meas[rxAnt][l].snr = 0;
prs_meas[rxAnt][l].dl_aoa = 0; prs_meas[rxAnt][l].dl_aoa = 0;
} // for rxAnt
} //for l
for (rxAnt=0; rxAnt < frame_params->nb_antennas_rx; rxAnt++)
{
#ifdef DEBUG_PRS_CHEST #ifdef DEBUG_PRS_CHEST
sprintf(filename, "%s%i%s", "PRSpilot_", rxAnt, ".m"); sprintf(filename, "%s%i%s", "PRSpilot_", rxAnt, ".m");
LOG_M(filename, "prs_loc", &mod_prs[0], prs_cfg->NumRB*(12/prs_cfg->CombSize),1,1); LOG_M(filename, "prs_loc", &mod_prs[0], prs_cfg->NumRB*(12/prs_cfg->CombSize),1,1);
@@ -438,10 +501,10 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
LOG_M(filename, varname, &rxdataF[rxAnt][prs_cfg->SymbolStart*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size,1,1); LOG_M(filename, varname, &rxdataF[rxAnt][prs_cfg->SymbolStart*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size,1,1);
sprintf(filename, "%s%i%s", "prsChestF_", rxAnt, ".m"); sprintf(filename, "%s%i%s", "prsChestF_", rxAnt, ".m");
sprintf(varname, "%s%i", "prsChF_", rxAnt); sprintf(varname, "%s%i", "prsChF_", rxAnt);
LOG_M(filename, varname, &prs_chestF[rxAnt][prs_cfg->SymbolStart*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size,1,1); LOG_M(filename, varname, &prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size], frame_params->ofdm_symbol_size,1,1);
sprintf(filename, "%s%i%s", "prsChestT_", rxAnt, ".m"); sprintf(filename, "%s%i%s", "prsChestT_", rxAnt, ".m");
sprintf(varname, "%s%i", "prsChT_", rxAnt); sprintf(varname, "%s%i", "prsChT_", rxAnt);
LOG_M(filename, varname, &prs_chestT[rxAnt][prs_cfg->SymbolStart*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size,1,1); LOG_M(filename, varname, &prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size], frame_params->ofdm_symbol_size,1,1);
#endif #endif
// T tracer dump // T tracer dump
@@ -451,23 +514,17 @@ int nr_prs_channel_estimation(uint8_t gNB_id,
T(T_UE_PHY_DL_CHANNEL_ESTIMATE_FREQ, T_INT(gNB_id), T(T_UE_PHY_DL_CHANNEL_ESTIMATE_FREQ, T_INT(gNB_id),
T_INT(proc->frame_rx), T_INT(proc->nr_slot_rx), T_INT(proc->frame_rx), T_INT(proc->nr_slot_rx),
T_INT(rxAnt), T_BUFFER(&prs_chestF[rxAnt][prs_cfg->SymbolStart*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size*sizeof(int32_t))); T_INT(rxAnt), T_BUFFER(&prs_chestF[rxAnt][l*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size*sizeof(int32_t)));
T(T_UE_PHY_DL_CHANNEL_ESTIMATE, T_INT(gNB_id), T(T_UE_PHY_DL_CHANNEL_ESTIMATE, T_INT(gNB_id),
T_INT(proc->frame_rx), T_INT(proc->nr_slot_rx), T_INT(proc->frame_rx), T_INT(proc->nr_slot_rx),
T_INT(rxAnt), T_BUFFER(&prs_chestT[rxAnt][prs_cfg->SymbolStart*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size*sizeof(int32_t))); T_INT(rxAnt), T_BUFFER(&prs_chestT[rxAnt][l*frame_params->ofdm_symbol_size], prs_cfg->NumPRSSymbols*frame_params->ofdm_symbol_size*sizeof(int32_t)));
} }
free(ch_freq); free(ch_tmp);
free(ch_time);
return(0); return(0);
} }
static inline int abs32(int x)
{
return (((int)((short*)&x)[0])*((int)((short*)&x)[0]) + ((int)((short*)&x)[1])*((int)((short*)&x)[1]));
}
/* Generic function to find the peak of channel estimation buffer */ /* Generic function to find the peak of channel estimation buffer */
void peak_estimator(int32_t *buffer, int32_t buf_len, int32_t *peak_idx, int32_t *peak_val) void peak_estimator(int32_t *buffer, int32_t buf_len, int32_t *peak_idx, int32_t *peak_val)