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#include "PHY/defs_gNB.h"
#include "PHY/NR_TRANSPORT/nr_transport_proto.h"
#include "PHY/LTE_REFSIG/lte_refsig.h"
#include "PHY/NR_REFSIG/nr_refsig.h"
#include "PHY/sse_intrin.h"
//#define DEBUG_PRS_MOD
//#define DEBUG_PRS_MAP
extern short nr_qpsk_mod_table[8];
int nr_generate_prs(uint32_t **nr_gold_prs,
c16_t *txdataF,
int16_t amp,
prs_config_t *prs_cfg,
nfapi_nr_config_request_scf_t *config,
NR_DL_FRAME_PARMS *frame_parms)
{
int k_prime = 0, k = 0, idx;
int16_t mod_prs[NR_MAX_PRS_LENGTH<<1];
int16_t k_prime_table[K_PRIME_TABLE_ROW_SIZE][K_PRIME_TABLE_COL_SIZE] = PRS_K_PRIME_TABLE;
// PRS resource mapping with combsize=k which means PRS symbols exist in every k-th subcarrier in frequency domain
// According to ts138.211 sec.7.4.1.7.2
for (int l = prs_cfg->SymbolStart; l < prs_cfg->SymbolStart + prs_cfg->NumPRSSymbols; l++) {
int symInd = l-prs_cfg->SymbolStart;
if (prs_cfg->CombSize == 2) {
k_prime = k_prime_table[0][symInd];
}
else if (prs_cfg->CombSize == 4){
k_prime = k_prime_table[1][symInd];
}
else if (prs_cfg->CombSize == 6){
k_prime = k_prime_table[2][symInd];
}
else if (prs_cfg->CombSize == 12){
k_prime = k_prime_table[3][symInd];
}
k = (prs_cfg->REOffset+k_prime) % prs_cfg->CombSize + prs_cfg->RBOffset*12 + frame_parms->first_carrier_offset;
// QPSK modulation
for (int m = 0; m < (12/prs_cfg->CombSize) * prs_cfg->NumRB; m++) {
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)+1] = nr_qpsk_mod_table[(idx<<1) + 1];
#ifdef DEBUG_PRS_MOD
LOG_D("m %d idx %d gold seq %d mod_prs %d %d\n", m, idx, nr_gold_prs[l][(m<<1)>>5], mod_prs[m<<1], mod_prs[(m<<1)+1]);
#endif
#ifdef DEBUG_PRS_MAP
LOG_D("m %d at k %d of l %d reIdx %d\n", m, k, l, (l*frame_parms->ofdm_symbol_size + k)<<1);
#endif
((int16_t *)txdataF)[(l*frame_parms->ofdm_symbol_size + k)<<1] = (amp * mod_prs[m<<1]) >> 15;
((int16_t *)txdataF)[((l*frame_parms->ofdm_symbol_size + k)<<1) + 1] = (amp * mod_prs[(m<<1) + 1]) >> 15;
#ifdef DEBUG_PRS_MAP
LOG_D("(%d,%d)\n",
((int16_t *)txdataF)[(l*frame_parms->ofdm_symbol_size + k)<<1],
((int16_t *)txdataF)[((l*frame_parms->ofdm_symbol_size + k)<<1)+1]);
#endif
k = k + prs_cfg->CombSize;
if (k >= frame_parms->ofdm_symbol_size)
k-=frame_parms->ofdm_symbol_size;
}
}
#ifdef DEBUG_PRS_MAP
LOG_M("nr_prs.m", "prs",(int16_t *)&txdataF[prs_cfg->SymbolStart*frame_parms->ofdm_symbol_size],prs_cfg->NumPRSSymbols*frame_parms->ofdm_symbol_size, 1, 1);
#endif
return 0;
}