int srslte_chest_ul_estimate_pucch(srslte_chest_ul_t *q, cf_t *input, cf_t *ce,
srslte_pucch_format_t format, uint32_t n_pucch, uint32_t sf_idx,
uint8_t *pucch2_ack_bits)
{
if (!q->dmrs_signal_configured) {
fprintf(stderr, "Error must call srslte_chest_ul_set_cfg() before using the UL estimator\n");
return SRSLTE_ERROR;
}
int n_rs = srslte_refsignal_dmrs_N_rs(format, q->cell.cp);
if (!n_rs) {
fprintf(stderr, "Error computing N_rs\n");
return SRSLTE_ERROR;
}
int nrefs_sf = SRSLTE_NRE*n_rs*2;
/* Get references from the input signal */
srslte_refsignal_dmrs_pucch_get(&q->dmrs_signal, format, n_pucch, input, q->pilot_recv_signal);
/* Generate known pilots */
uint8_t pucch2_bits[2] = {0, 0};
if (format == SRSLTE_PUCCH_FORMAT_2A || format == SRSLTE_PUCCH_FORMAT_2B) {
float max = -1e9;
int i_max = 0;
int m = 0;
if (format == SRSLTE_PUCCH_FORMAT_2A) {
m = 2;
} else {
m = 4;
}
for (int i=0;i<m;i++) {
pucch2_bits[0] = i%2;
pucch2_bits[1] = i/2;
srslte_refsignal_dmrs_pucch_gen(&q->dmrs_signal, format, n_pucch, sf_idx, pucch2_bits, q->pilot_known_signal);
srslte_vec_prod_conj_ccc(q->pilot_recv_signal, q->pilot_known_signal, q->pilot_estimates_tmp[i], nrefs_sf);
float x = cabsf(srslte_vec_acc_cc(q->pilot_estimates_tmp[i], nrefs_sf));
if (x >= max) {
max = x;
i_max = i;
}
}
memcpy(q->pilot_estimates, q->pilot_estimates_tmp[i_max], nrefs_sf*sizeof(cf_t));
pucch2_ack_bits[0] = i_max%2;
pucch2_ack_bits[1] = i_max/2;
} else {
srslte_refsignal_dmrs_pucch_gen(&q->dmrs_signal, format, n_pucch, sf_idx, pucch2_bits, q->pilot_known_signal);
/* Use the known DMRS signal to compute Least-squares estimates */
srslte_vec_prod_conj_ccc(q->pilot_recv_signal, q->pilot_known_signal, q->pilot_estimates, nrefs_sf);
}
if (ce != NULL) {
/* FIXME: Currently averaging entire slot, performance good enough? */
for (int ns=0;ns<2;ns++) {
// Average all slot
for (int i=1;i<n_rs;i++) {
srslte_vec_sum_ccc(&q->pilot_estimates[ns*n_rs*SRSLTE_NRE], &q->pilot_estimates[(i+ns*n_rs)*SRSLTE_NRE],
&q->pilot_estimates[ns*n_rs*SRSLTE_NRE],
SRSLTE_NRE);
}
srslte_vec_sc_prod_ccc(&q->pilot_estimates[ns*n_rs*SRSLTE_NRE], (float) 1.0/n_rs,
&q->pilot_estimates[ns*n_rs*SRSLTE_NRE],
SRSLTE_NRE);
// Average in freq domain
srslte_chest_average_pilots(&q->pilot_estimates[ns*n_rs*SRSLTE_NRE], &q->pilot_recv_signal[ns*n_rs*SRSLTE_NRE],
q->smooth_filter, SRSLTE_NRE, 1, q->smooth_filter_len);
// Determine n_prb
uint32_t n_prb = srslte_pucch_n_prb(&q->dmrs_signal.pucch_cfg, format, n_pucch, q->cell.nof_prb, q->cell.cp, ns);
// copy estimates to slot
for (int i=0;i<SRSLTE_CP_NSYMB(q->cell.cp);i++) {
memcpy(&ce[SRSLTE_RE_IDX(q->cell.nof_prb, i+ns*SRSLTE_CP_NSYMB(q->cell.cp), n_prb*SRSLTE_NRE)],
&q->pilot_recv_signal[ns*n_rs*SRSLTE_NRE], sizeof(cf_t)*SRSLTE_NRE);
}
}
}
return 0;
}
int main(int argc, char **argv) {
srslte_pucch_t pucch;
srslte_pucch_cfg_t pucch_cfg;
srslte_refsignal_ul_t dmrs;
uint8_t bits[SRSLTE_PUCCH_MAX_BITS];
uint8_t pucch2_bits[2];
cf_t *sf_symbols = NULL;
cf_t pucch_dmrs[2*SRSLTE_NRE*3];
int ret = -1;
parse_args(argc,argv);
if (srslte_pucch_init(&pucch, cell)) {
fprintf(stderr, "Error creating PDSCH object\n");
goto quit;
}
if (srslte_refsignal_ul_init(&dmrs, cell)) {
fprintf(stderr, "Error creating PDSCH object\n");
goto quit;
}
bzero(&pucch_cfg, sizeof(srslte_pucch_cfg_t));
for (int i=0;i<SRSLTE_PUCCH_MAX_BITS;i++) {
bits[i] = i%2;
}
for (int i=0;i<2;i++) {
pucch2_bits[i] = i%2;
}
if (srslte_pucch_set_crnti(&pucch, 11)) {
fprintf(stderr, "Error setting C-RNTI\n");
goto quit;
}
sf_symbols = srslte_vec_malloc(sizeof(cf_t) * SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp));
if (!sf_symbols) {
goto quit;
}
srslte_pucch_format_t format;
for (format=0;format<=SRSLTE_PUCCH_FORMAT_2B;format++) {
for (uint32_t d=1;d<=3;d++) {
for (uint32_t ncs=0;ncs<8;ncs+=d) {
for (uint32_t n_pucch=1;n_pucch<130;n_pucch+=50) {
struct timeval t[3];
pucch_cfg.delta_pucch_shift = d;
bool group_hopping_en = false;
pucch_cfg.N_cs = ncs;
pucch_cfg.n_rb_2 = 0;
gettimeofday(&t[1], NULL);
if (!srslte_pucch_set_cfg(&pucch, &pucch_cfg, group_hopping_en)) {
fprintf(stderr, "Error setting PUCCH config\n");
goto quit;
}
if (srslte_pucch_encode(&pucch, format, n_pucch, subframe, bits, sf_symbols)) {
fprintf(stderr, "Error encoding PUCCH\n");
goto quit;
}
srslte_refsignal_dmrs_pusch_cfg_t pusch_cfg;
pusch_cfg.group_hopping_en = group_hopping_en;
pusch_cfg.sequence_hopping_en = false;
srslte_refsignal_ul_set_cfg(&dmrs, &pusch_cfg, &pucch_cfg, NULL);
if (srslte_refsignal_dmrs_pucch_gen(&dmrs, format, n_pucch, subframe, pucch2_bits, pucch_dmrs)) {
fprintf(stderr, "Error encoding PUCCH\n");
goto quit;
}
if (srslte_refsignal_dmrs_pucch_put(&dmrs, format, n_pucch, pucch_dmrs, sf_symbols)) {
fprintf(stderr, "Error encoding PUCCH\n");
goto quit;
}
gettimeofday(&t[2], NULL);
get_time_interval(t);
INFO("format %d, n_pucch: %d, ncs: %d, d: %d, t_exec=%d us\n", format, n_pucch, ncs, d, t[0].tv_usec);
}
}
}
}
ret = 0;
quit:
srslte_pucch_free(&pucch);
srslte_refsignal_ul_free(&dmrs);
if (sf_symbols) {
free(sf_symbols);
}
if (ret) {
printf("Error\n");
} else {
printf("Ok\n");
}
exit(ret);
}
