static int srslte_pdsch_codeword_encode(srslte_pdsch_t *q, srslte_pdsch_cfg_t *cfg,
srslte_softbuffer_tx_t *softbuffer, uint16_t rnti, uint8_t *data,
uint32_t codeword_idx, uint32_t tb_idx) {
srslte_ra_nbits_t *nbits = &cfg->nbits[tb_idx];
srslte_ra_mcs_t *mcs = &cfg->grant.mcs[tb_idx];
uint32_t rv = cfg->rv[tb_idx];
bool valid_inputs = true;
if (!softbuffer) {
ERROR("Error encoding (TB%d -> CW%d), softbuffer=NULL", tb_idx, codeword_idx);
valid_inputs = false;
}
if (nbits->nof_bits && valid_inputs) {
INFO("Encoding PDSCH SF: %d (TB%d -> CW%d), Mod %s, NofBits: %d, NofSymbols: %d, NofBitsE: %d, rv_idx: %d\n",
cfg->sf_idx, tb_idx, codeword_idx, srslte_mod_string(mcs->mod), mcs->tbs,
nbits->nof_re, nbits->nof_bits, rv);
/* Channel coding */
if (srslte_dlsch_encode2(&q->dl_sch, cfg, softbuffer, data, q->e[codeword_idx], tb_idx)) {
ERROR("Error encoding (TB%d -> CW%d)", tb_idx, codeword_idx);
return SRSLTE_ERROR;
}
/* Select scrambling sequence */
srslte_sequence_t *seq = get_user_sequence(q, rnti, codeword_idx, cfg->sf_idx, nbits->nof_bits);
/* Bit scrambling */
srslte_scrambling_bytes(seq, (uint8_t *) q->e[codeword_idx], nbits->nof_bits);
/* Bit mapping */
srslte_mod_modulate_bytes(&q->mod[mcs->mod],
(uint8_t *) q->e[codeword_idx],
q->d[codeword_idx], nbits->nof_bits);
} else {
return SRSLTE_ERROR_INVALID_INPUTS;
}
return SRSLTE_SUCCESS;
}
int srslte_pmch_encode(srslte_pmch_t *q,
srslte_pdsch_cfg_t *cfg, srslte_softbuffer_tx_t *softbuffer,
uint8_t *data, uint16_t area_id, cf_t *sf_symbols[SRSLTE_MAX_PORTS])
{
int i;
/* Set pointers for layermapping & precoding */
cf_t *x[SRSLTE_MAX_LAYERS];
int ret = SRSLTE_ERROR_INVALID_INPUTS;
if (q != NULL && cfg != NULL)
{
for (i=0;i<q->cell.nof_ports;i++) {
if (sf_symbols[i] == NULL) {
return SRSLTE_ERROR_INVALID_INPUTS;
}
}
if (cfg->grant.mcs[0].tbs == 0) {
return SRSLTE_ERROR_INVALID_INPUTS;
}
if (cfg->nbits[0].nof_re > q->max_re) {
fprintf(stderr,
"Error too many RE per subframe (%d). PMCH configured for %d RE (%d PRB)\n",
cfg->nbits[0].nof_re, q->max_re, q->cell.nof_prb);
return SRSLTE_ERROR_INVALID_INPUTS;
}
INFO("Encoding PMCH SF: %d, Mod %s, NofBits: %d, NofSymbols: %d, NofBitsE: %d, rv_idx: %d\n",
cfg->sf_idx, srslte_mod_string(cfg->grant.mcs[0].mod), cfg->grant.mcs[0].tbs,
cfg->nbits[0].nof_re, cfg->nbits[0].nof_bits, 0);
/* number of layers equals number of ports */
for (i = 0; i < q->cell.nof_ports; i++) {
x[i] = q->x[i];
}
memset(&x[q->cell.nof_ports], 0, sizeof(cf_t*) * (SRSLTE_MAX_LAYERS - q->cell.nof_ports));
// TODO: use tb_encode directly
if (srslte_dlsch_encode(&q->dl_sch, cfg, softbuffer, data, q->e)) {
fprintf(stderr, "Error encoding TB\n");
return SRSLTE_ERROR;
}
/* scramble */
srslte_scrambling_bytes(&q->seqs[area_id]->seq[cfg->sf_idx], (uint8_t*) q->e, cfg->nbits[0].nof_bits);
srslte_mod_modulate_bytes(&q->mod[cfg->grant.mcs[0].mod], (uint8_t*) q->e, q->d, cfg->nbits[0].nof_bits);
/* No tx diversity in MBSFN */
memcpy(q->symbols[0], q->d, cfg->nbits[0].nof_re * sizeof(cf_t));
/* mapping to resource elements */
for (i = 0; i < q->cell.nof_ports; i++) {
srslte_pmch_put(q, q->symbols[i], sf_symbols[i], cfg->nbits[0].lstart);
}
ret = SRSLTE_SUCCESS;
}
return ret;
}
int main(int argc, char **argv) {
int i;
srslte_modem_table_t mod;
uint8_t *input, *input_bytes, *output;
cf_t *symbols, *symbols_bytes;
float *llr, *llr2;
parse_args(argc, argv);
/* initialize objects */
if (srslte_modem_table_lte(&mod, modulation)) {
fprintf(stderr, "Error initializing modem table\n");
exit(-1);
}
srslte_modem_table_bytes(&mod);
/* check that num_bits is multiple of num_bits x symbol */
if (num_bits % mod.nbits_x_symbol) {
fprintf(stderr, "Error num_bits must be multiple of %d\n", mod.nbits_x_symbol);
exit(-1);
}
/* allocate buffers */
input = srslte_vec_malloc(sizeof(uint8_t) * num_bits);
if (!input) {
perror("malloc");
exit(-1);
}
input_bytes = srslte_vec_malloc(sizeof(uint8_t) * num_bits/8);
if (!input_bytes) {
perror("malloc");
exit(-1);
}
output = srslte_vec_malloc(sizeof(uint8_t) * num_bits);
if (!output) {
perror("malloc");
exit(-1);
}
symbols = srslte_vec_malloc(sizeof(cf_t) * num_bits / mod.nbits_x_symbol);
if (!symbols) {
perror("malloc");
exit(-1);
}
symbols_bytes = srslte_vec_malloc(sizeof(cf_t) * num_bits / mod.nbits_x_symbol);
if (!symbols_bytes) {
perror("malloc");
exit(-1);
}
llr = srslte_vec_malloc(sizeof(float) * num_bits);
if (!llr) {
perror("malloc");
exit(-1);
}
llr2 = srslte_vec_malloc(sizeof(float) * num_bits);
if (!llr2) {
perror("malloc");
exit(-1);
}
/* generate random data */
for (i=0;i<num_bits;i++) {
input[i] = rand()%2;
}
/* modulate */
struct timeval t[3];
gettimeofday(&t[1], NULL);
int ntrials = 100;
for (int i=0;i<ntrials;i++) {
srslte_mod_modulate(&mod, input, symbols, num_bits);
}
gettimeofday(&t[2], NULL);
get_time_interval(t);
printf("Bit: %d us\n", t[0].tv_usec);
/* Test packed implementation */
srslte_bit_pack_vector(input, input_bytes, num_bits);
gettimeofday(&t[1], NULL);
for (int i=0;i<ntrials;i++) {
srslte_mod_modulate_bytes(&mod, input_bytes, symbols_bytes, num_bits);
}
gettimeofday(&t[2], NULL);
get_time_interval(t);
printf("Byte: %d us\n", t[0].tv_usec);
for (int i=0;i<num_bits/mod.nbits_x_symbol;i++) {
if (symbols[i] != symbols_bytes[i]) {
printf("error in symbol %d\n", i);
exit(-1);
}
}
printf("Symbols OK\n");
/* demodulate */
gettimeofday(&x, NULL);
srslte_demod_soft_demodulate(modulation, symbols, llr, num_bits / mod.nbits_x_symbol);
gettimeofday(&y, NULL);
printf("\nElapsed time [ns]: %d\n", (int) y.tv_usec - (int) x.tv_usec);
for (i=0;i<num_bits;i++) {
output[i] = llr[i]>=0 ? 1 : 0;
}
/* check errors */
for (i=0;i<num_bits;i++) {
if (input[i] != output[i]) {
fprintf(stderr, "Error in bit %d\n", i);
exit(-1);
}
}
free(llr);
free(symbols);
free(symbols_bytes);
free(output);
free(input);
free(input_bytes);
srslte_modem_table_free(&mod);
printf("Ok\n");
exit(0);
}
/** Converts the PDSCH data bits to symbols mapped to the slot ready for transmission
*/
int srslte_pdsch_encode_rnti(srslte_pdsch_t *q,
srslte_pdsch_cfg_t *cfg, srslte_softbuffer_tx_t *softbuffer,
uint8_t *data, uint16_t rnti, cf_t *sf_symbols[SRSLTE_MAX_PORTS])
{
int i;
/* Set pointers for layermapping & precoding */
cf_t *x[SRSLTE_MAX_LAYERS];
int ret = SRSLTE_ERROR_INVALID_INPUTS;
if (q != NULL &&
data != NULL &&
cfg != NULL)
{
for (i=0; i<q->cell.nof_ports; i++) {
if (sf_symbols[i] == NULL) {
return SRSLTE_ERROR_INVALID_INPUTS;
}
}
if (cfg->grant.mcs.tbs == 0) {
return SRSLTE_ERROR_INVALID_INPUTS;
}
if (cfg->nbits.nof_re > q->max_re) {
fprintf(stderr,
"Error too many RE per subframe (%d). PDSCH configured for %d RE (%d PRB)\n",
cfg->nbits.nof_re, q->max_re, q->cell.nof_prb);
return SRSLTE_ERROR_INVALID_INPUTS;
}
INFO("Encoding PDSCH SF: %d, Mod %s, NofBits: %d, NofSymbols: %d, NofBitsE: %d, rv_idx: %d\n",
cfg->sf_idx, srslte_mod_string(cfg->grant.mcs.mod), cfg->grant.mcs.tbs,
cfg->nbits.nof_re, cfg->nbits.nof_bits, cfg->rv);
/* number of layers equals number of ports */
for (i = 0; i < q->cell.nof_ports; i++) {
x[i] = q->x[i];
}
memset(&x[q->cell.nof_ports], 0, sizeof(cf_t*) * (SRSLTE_MAX_LAYERS - q->cell.nof_ports));
if (srslte_dlsch_encode(&q->dl_sch, cfg, softbuffer, data, q->e)) {
fprintf(stderr, "Error encoding TB\n");
return SRSLTE_ERROR;
}
if (rnti != q->rnti) {
srslte_sequence_t seq;
if (srslte_sequence_pdsch(&seq, rnti, 0, 2 * cfg->sf_idx, q->cell.id, cfg->nbits.nof_bits)) {
return SRSLTE_ERROR;
}
srslte_scrambling_bytes_offset(&seq, (uint8_t*) q->e, 0, cfg->nbits.nof_bits);
srslte_sequence_free(&seq);
} else {
srslte_scrambling_bytes_offset(&q->seq[cfg->sf_idx], (uint8_t*) q->e, 0, cfg->nbits.nof_bits);
}
srslte_mod_modulate_bytes(&q->mod[cfg->grant.mcs.mod], (uint8_t*) q->e, q->d, cfg->nbits.nof_bits);
/* TODO: only diversity supported */
if (q->cell.nof_ports > 1) {
srslte_layermap_diversity(q->d, x, q->cell.nof_ports, cfg->nbits.nof_re);
srslte_precoding_diversity(&q->precoding, x, q->symbols, q->cell.nof_ports,
cfg->nbits.nof_re / q->cell.nof_ports);
} else {
memcpy(q->symbols[0], q->d, cfg->nbits.nof_re * sizeof(cf_t));
}
/* mapping to resource elements */
for (i = 0; i < q->cell.nof_ports; i++) {
srslte_pdsch_put(q, q->symbols[i], sf_symbols[i], &cfg->grant, cfg->nbits.lstart, cfg->sf_idx);
}
ret = SRSLTE_SUCCESS;
}
return ret;
}
