PentHertz
/
srsLTE
mirror of https://github.com/PentHertz/srsLTE.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix NR SCH Nref calculation

This commit is contained in:
Xavier Arteaga 2021-05-04 13:15:21 +02:00 committed by Xavier Arteaga
parent 0ecb3a7220
commit 9e1a85afe8
1 changed files with 45 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
lib/src/phy/phch/sch_nr.c
View File

@ -65,6 +65,43 @@ uint32_t sch_nr_n_prb_lbrm(uint32_t nof_prb)
return 273;
}
static int sch_nr_cbsegm(srsran_basegraph_t bg, uint32_t tbs, srsran_cbsegm_t* cbsegm)
{
if (bg == BG1) {
if (srsran_cbsegm_ldpc_bg1(cbsegm, tbs) != SRSRAN_SUCCESS) {
ERROR("Error: calculating LDPC BG1 code block segmentation for tbs=%d", tbs);
return SRSRAN_ERROR;
}
} else {
if (srsran_cbsegm_ldpc_bg2(cbsegm, tbs) != SRSRAN_SUCCESS) {
ERROR("Error: calculating LDPC BG1 code block segmentation for tbs=%d", tbs);
return SRSRAN_ERROR;
}
}
return SRSRAN_SUCCESS;
}
static int sch_nr_Nref(uint32_t N_rb, srsran_mcs_table_t mcs_table, uint32_t max_mimo_layers)
{
uint32_t N_re_lbrm = SRSRAN_MAX_NRE_NR * sch_nr_n_prb_lbrm(N_rb);
double TCR_lbrm = 948.0 / 1024.0;
uint32_t Qm_lbrm = (mcs_table == srsran_mcs_table_256qam) ? 8 : 6;
uint32_t TBS_LRBM = srsran_ra_nr_tbs(N_re_lbrm, 1.0, TCR_lbrm, Qm_lbrm, max_mimo_layers);
double R = 2.0 / 3.0;
srsran_basegraph_t bg = srsran_sch_nr_select_basegraph(TBS_LRBM, R);
// Compute segmentation
srsran_cbsegm_t cbsegm = {};
int r = sch_nr_cbsegm(bg, TBS_LRBM, &cbsegm);
if (r < SRSRAN_SUCCESS) {
ERROR("Error computing TB segmentation");
return SRSRAN_ERROR;
}
return (int)ceil((double)TBS_LRBM / (double)(cbsegm.C * R));
}
int srsran_sch_nr_fill_tb_info(const srsran_carrier_nr_t* carrier,
const srsran_sch_cfg_t* sch_cfg,
const srsran_sch_tb_t* tb,
@ -79,16 +116,9 @@ int srsran_sch_nr_fill_tb_info(const srsran_carrier_nr_t* carrier,
// Compute code block segmentation
srsran_cbsegm_t cbsegm = {};
if (bg == BG1) {
if (srsran_cbsegm_ldpc_bg1(&cbsegm, tb->tbs) != SRSRAN_SUCCESS) {
ERROR("Error: calculating LDPC BG1 code block segmentation for tbs=%d", tb->tbs);
return SRSRAN_ERROR;
}
} else {
if (srsran_cbsegm_ldpc_bg2(&cbsegm, tb->tbs) != SRSRAN_SUCCESS) {
ERROR("Error: calculating LDPC BG1 code block segmentation for tbs=%d", tb->tbs);
return SRSRAN_ERROR;
}
if (sch_nr_cbsegm(bg, tb->tbs, &cbsegm) < SRSRAN_SUCCESS) {
ERROR("Error calculation TB segmentation");
return SRSRAN_ERROR;
}
if (cbsegm.Z > MAX_LIFTSIZE) {
@ -111,13 +141,11 @@ int srsran_sch_nr_fill_tb_info(const srsran_carrier_nr_t* carrier,
cfg->Nl = tb->N_L;
// Calculate Nref
uint32_t N_re_lbrm = SRSRAN_MAX_NRE_NR * sch_nr_n_prb_lbrm(carrier->nof_prb);
double TCR_lbrm = 948.0 / 1024.0;
uint32_t Qm_lbrm = (sch_cfg->mcs_table == srsran_mcs_table_256qam) ? 8 : 6;
uint32_t max_mimo_layers = SRSRAN_MAX(carrier->max_mimo_layers, 4);
uint32_t TBS_LRBM = srsran_ra_nr_tbs(N_re_lbrm, 1.0, TCR_lbrm, Qm_lbrm, max_mimo_layers);
double R = 2.0 / 3.0;
cfg->Nref = (uint32_t)ceil((double)TBS_LRBM / (double)(cbsegm.C * R));
int Nref = sch_nr_Nref(carrier->nof_prb, sch_cfg->mcs_table, carrier->max_mimo_layers);
if (Nref < SRSRAN_SUCCESS) {
ERROR("Error computing N_ref");
}
cfg->Nref = (uint32_t)Nref;
// Calculate number of code blocks after applying CBGTI... not implemented, activate all CB
for (uint32_t r = 0; r < cbsegm.C; r++) {
@ -656,7 +684,6 @@ static int sch_nr_decode(srsran_sch_nr_t* q,
res->avg_iter = NAN;
}
// Not all CB are decoded, skip TB union and CRC check
if (cb_ok != cfg.C) {
return SRSRAN_SUCCESS;