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Shifting the QAM threshold by AMP, instead of shifting the data by AMP_SHIFT

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This fixes the errors in bits introduced after LDPC decoding in case of mod_order = 6 and AMO_SHIFT = 9
This commit is contained in:
Ahmed Hussein
2019-06-04 13:43:19 +02:00
committed by Thomas Schlichter
parent 63a2e61101
commit 176d873083
4 changed files with 8 additions and 13 deletions
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openair1/PHY/NR_TRANSPORT/nr_ulsch_demodulation.c
+2 -4
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@@ -4,7 +4,6 @@
#include "PHY/NR_TRANSPORT/nr_sch_dmrs.h"
void nr_ulsch_extract_rbs_single(int **rxdataF,
int **rxdataF_ext,
uint32_t rxdataF_ext_offset,
@@ -35,9 +34,8 @@ void nr_ulsch_extract_rbs_single(int **rxdataF,
if ( (is_dmrs_symbol && ((re&1) != frame_parms->nushift)) || (is_dmrs_symbol == 0) ) { // [hna] (re&1) != frame_parms->nushift) assuming only dmrs type 1 and mapping type A
rxF_ext[rxF_ext_index] = (rxF[ ((start_re + re)*2) % (frame_parms->ofdm_symbol_size*2)] << 15) >> AMP_SHIFT;
rxF_ext[rxF_ext_index + 1] = (rxF[(((start_re + re)*2) + 1) % (frame_parms->ofdm_symbol_size*2)] << 15) >> AMP_SHIFT;
rxF_ext[rxF_ext_index] = (rxF[ ((start_re + re)*2) % (frame_parms->ofdm_symbol_size*2)]);
rxF_ext[rxF_ext_index + 1] = (rxF[(((start_re + re)*2) + 1) % (frame_parms->ofdm_symbol_size*2)]);
rxF_ext_index = rxF_ext_index + 2;
}
}
openair1/PHY/NR_TRANSPORT/nr_ulsch_llr_computation.c
+5 -6
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@@ -116,8 +116,8 @@ void nr_ulsch_16qam_llr(int32_t *rxdataF_comp,
nb_re >>= 2; // length in quad words (4 REs)
nb_re += (len_mod4 == 0 ? 0 : 1);
temp_channel = _mm_set1_epi16((int16_t)((QAM16_n1 * one_over_sqrt_2)>>15));
temp_channel = _mm_set1_epi16((QAM16_n1 * one_over_sqrt_2)>>(2*15-AMP_SHIFT));
for (i=0; i<nb_re; i++) {
#if defined(__x86_64__) || defined(__i386)
@@ -222,9 +222,8 @@ void nr_ulsch_64qam_llr(int32_t *rxdataF_comp,
nb_re = nb_re>>2; // length in quad words (4 REs)
nb_re += ((len_mod4 == 0) ? 0 : 1);
temp_channel[0] = _mm_set1_epi16((int16_t)((QAM64_n1 * one_over_sqrt_2)>>15));
temp_channel[1] = _mm_set1_epi16((int16_t)((QAM64_n2 * one_over_sqrt_2)>>15));
temp_channel[0] = _mm_set1_epi16((QAM64_n1 * one_over_sqrt_2)>>(2*15-AMP_SHIFT));
temp_channel[1] = _mm_set1_epi16((QAM64_n2 * one_over_sqrt_2)>>(2*15-AMP_SHIFT));
for (i=0; i<nb_re; i++) {
@@ -362,4 +361,4 @@ void nr_ulsch_compute_llr(int32_t *rxdataF_comp,
LOG_E(PHY,"nr_ulsch_compute_llr: invalid Qm value, symbol = %d, Qm = %d\n",symbol, mod_order);
break;
}
}
}
openair1/PHY/impl_defs_top.h
+1 -1
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@@ -245,7 +245,7 @@
#ifdef BIT8_TX
#define AMP_SHIFT 7
#else
#define AMP_SHIFT 10 // [hna] was 9, but 9 doesn't work in case of mod_order = 6 (problem due to IFFT/FFT)
#define AMP_SHIFT 9
#endif
#define AMP ((1)<<AMP_SHIFT)
openair1/SCHED_NR/phy_procedures_nr_gNB.c
-2
View File
@@ -216,8 +216,6 @@ void nr_ulsch_procedures(PHY_VARS_gNB *gNB, gNB_L1_rxtx_proc_t *proc, int UE_id,
//----------------------------------------------------------
nr_ulsch_unscrambling(gNB->pusch_vars[UE_id]->llr, gNB->ulsch[UE_id+1][0]->harq_processes[harq_pid]->G, 0, Nid_cell, rel15_ul->rnti);
////////////////////////////////////////////////////////////
//----------------------------------------------------------