Files
openairinterface5g/openair1/PHY/NR_TRANSPORT/nr_tbs_tools.c
2026-07-09 07:57:51 +02:00

73 lines
1.9 KiB
C

/*
* SPDX-License-Identifier: LicenseRef-CSSL-1.0
*/
/*!
* \brief Top-level routines for implementing LDPC-coded (DLSCH) transport channels from 38-212, 15.2
*/
#include "nr_transport_common_proto.h"
#include "PHY/CODING/coding_defs.h"
#include "PHY/defs_nr_common.h"
#include "log.h"
uint32_t
nr_get_G(uint16_t nb_rb, uint16_t nb_symb_sch, uint8_t nb_re_dmrs, uint16_t length_dmrs, uint32_t unav_res, uint8_t Qm, uint8_t Nl)
{
uint32_t G = ((NR_NB_SC_PER_RB * nb_symb_sch) - (nb_re_dmrs * length_dmrs)) * nb_rb * Qm * Nl;
G -= unav_res * Qm * Nl;
return (G);
}
int nr_get_E(uint32_t G, uint8_t C, uint8_t Qm, uint8_t Nl, uint8_t r)
{
if (Nl <= 0 || Qm <= 0) {
LOG_E(PHY, "Invalid input parameter in nr_get_E: Qm %d Nl %d\n", Qm, Nl);
return -1;
}
uint32_t E;
uint8_t Cprime = C; // assume CBGTI not present
if (r <= Cprime - ((G / (Nl * Qm)) % Cprime) - 1)
E = Nl * Qm * (G / (Nl * Qm * Cprime));
else
E = Nl * Qm * ((G / (Nl * Qm * Cprime)) + 1);
LOG_D(PHY, "nr_get_E : (G %d, C %d, Qm %d, Nl %d, r %d), E %d\n", G, C, Qm, Nl, r, E);
return E;
}
static const uint8_t index_k0[2][4] = {{0, 17, 33, 56}, {0, 13, 25, 43}};
int nr_get_R_ldpc_decoder(int rvidx, int E, int BG, int Z, int *llrLen, int round)
{
AssertFatal(BG == 1 || BG == 2, "Unknown BG %d\n", BG);
int Ncb = (BG == 1) ? (66 * Z) : (50 * Z);
int infoBits = (index_k0[BG - 1][rvidx] * Z + E);
if (round == 0)
*llrLen = infoBits;
if (infoBits > Ncb)
infoBits = Ncb;
if (infoBits > *llrLen)
*llrLen = infoBits;
int sysBits = (BG == 1) ? (22 * Z) : (10 * Z);
float decoderR = (float)sysBits / (infoBits + 2 * Z);
if (BG == 2)
if (decoderR < 0.3333)
return 15;
else if (decoderR < 0.6667)
return 13;
else
return 23;
else if (decoderR < 0.6667)
return 13;
else if (decoderR < 0.8889)
return 23;
else
return 89;
}