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Fix channel estimation for 3/4 sampling

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In 3/4 sampling mode, the OFDM symbol size is _not_ a power of two (e.g. 1536 instead of 2048).
In this case it is _not_ OK to calculate the modulus using a binary AND, it _must_ use either the actul modulus operator (%) using an integer division,
or a _correct_ if statement or tertianary operator like this:

re_offset = (re_offset + 4 >= ue->frame_parms.ofdm_symbol_size) ? (re_offset + 4 - ue->frame_parms.ofdm_symbol_size) : (re_offset + 4);

But of course using the actual modulus operator is much more readable and surely not much slower:

re_offset = (re_offset + 4) % ue->frame_parms.ofdm_symbol_size;
This commit is contained in:
Thomas Schlichter
2019-11-14 17:32:09 +01:00
parent 348afdc17e
commit ef3be74025
2 changed files with 35 additions and 56 deletions
Download Patch File Download Diff File Expand all files Collapse all files
openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c
+10 -10
View File
@@ -140,7 +140,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
ul_ch,
8);
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
//for (int i= 0; i<8; i++)
//printf("ul_ch addr %p %d\n", ul_ch+i, *(ul_ch+i));
@@ -156,7 +156,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
ul_ch,
8);
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
//printf("ul_ch addr %p\n",ul_ch);
@@ -175,7 +175,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
//printf("ul_ch addr %p %d\n", ul_ch+i, *(ul_ch+i));
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ul_ch+=8;
@@ -193,7 +193,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
8);
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
@@ -206,7 +206,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
ul_ch,
8);
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ul_ch+=8;
@@ -227,7 +227,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
//printf("ul_ch addr %p %d\n", ul_ch+i, *(ul_ch+i));
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
@@ -242,7 +242,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
8);
pil+=2;
re_offset = (re_offset+2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ul_ch+=8;
@@ -267,7 +267,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
pil += (idxPil-2);
ul_ch += (idxDC-4);
ul_ch = memset(ul_ch, 0, sizeof(int16_t)*10);
re_offset = (re_offset+idxDC/2-2)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+idxDC/2-2) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
ch[1] = (int16_t)(((int32_t)pil[0]*rxF[1] + (int32_t)pil[1]*rxF[0])>>15);
@@ -281,7 +281,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
8);
pil += 4;
re_offset = (re_offset+4)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+4) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
ch[1] = (int16_t)(((int32_t)pil[0]*rxF[1] + (int32_t)pil[1]*rxF[0])>>15);
@@ -298,7 +298,7 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
8);
pil += 4;
re_offset = (re_offset+4)&(gNB->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+4) % gNB->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
ch[1] = (int16_t)(((int32_t)pil[0]*rxF[1] + (int32_t)pil[1]*rxF[0])>>15);
openair1/PHY/NR_UE_ESTIMATION/nr_dl_channel_estimation.c
+25 -46
View File
@@ -98,8 +98,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
#endif
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
@@ -114,8 +113,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
#endif
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
current_ssb->c_re +=ch[0];
@@ -126,8 +124,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
#endif
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
for (pilot_cnt=3; pilot_cnt<(3*20); pilot_cnt+=3) {
@@ -138,8 +135,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
// in 2nd symbol, skip middle REs (48 with DMRS, 144 for SSS, and another 48 with DMRS)
if (dmrss == 1 && pilot_cnt == 12) {
pilot_cnt=48;
//re_offset = (re_offset+144)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 144) : (re_offset+144);
re_offset = (re_offset+144) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
}
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
@@ -153,8 +149,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
#endif
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
@@ -168,8 +163,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
printf("pilot %u : rxF - > (%d,%d) ch -> (%d,%d), pil -> (%d,%d) \n",pilot_cnt+1,rxF[0],rxF[1],ch[0],ch[1],pil[0],pil[1]);
#endif
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
@@ -184,8 +178,7 @@ int nr_pbch_dmrs_correlation(PHY_VARS_NR_UE *ue,
#endif
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
}
@@ -314,8 +307,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
16);
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
//for (int i= 0; i<8; i++)
@@ -333,8 +325,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
16);
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
@@ -349,8 +340,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
16);
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
dl_ch+=24;
@@ -362,8 +352,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
// in 2nd symbol, skip middle REs (48 with DMRS, 144 for SSS, and another 48 with DMRS)
if (dmrss == 1 && pilot_cnt == 12) {
pilot_cnt=48;
//re_offset = (re_offset+144)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 144) : (re_offset+144);
re_offset = (re_offset+144) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
dl_ch += 288;
}
@@ -382,8 +371,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
// printf("pilot_cnt %d dl_ch %d %d\n", pilot_cnt, dl_ch+i, *(dl_ch+i));
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
@@ -398,8 +386,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
16);
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
@@ -415,8 +402,7 @@ int nr_pbch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
16);
pil+=2;
//re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 4) : (re_offset+4);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+re_offset)];
dl_ch+=24;
@@ -731,7 +717,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
for (aarx=0; aarx<ue->frame_parms.nb_antennas_rx; aarx++) {
pil = (int16_t *)&pilot[rb_offset*((config_type==0) ? 6:4)];
k = k&(ue->frame_parms.ofdm_symbol_size-1);
k = k % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+k+nushift)];
dl_ch = (int16_t *)&dl_ch_estimates[aarx][ch_offset];
@@ -761,8 +747,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
8);
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
//for (int i= 0; i<8; i++)
//printf("dl_ch addr %p %d\n", dl_ch+i, *(dl_ch+i));
@@ -777,8 +762,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
8);
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
//printf("dl_ch addr %p\n",dl_ch);
@@ -796,8 +780,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
//printf("dl_ch addr %p %d\n", dl_ch+i, *(dl_ch+i));
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
dl_ch+=8;
@@ -817,8 +800,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
8);
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
@@ -831,8 +813,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
dl_ch,
8);
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
dl_ch+=8;
@@ -853,8 +834,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
//printf("dl_ch addr %p %d\n", dl_ch+i, *(dl_ch+i));
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
@@ -869,8 +849,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
8);
pil+=2;
re_offset = (re_offset+2)&(ue->frame_parms.ofdm_symbol_size-1);
//re_offset = (re_offset >= ue->frame_parms.ofdm_symbol_size) ? (re_offset - ue->frame_parms.ofdm_symbol_size + 2) : (re_offset+2);
re_offset = (re_offset+2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
dl_ch+=8;
@@ -895,7 +874,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
pil += (idxPil-2);
dl_ch += (idxDC-4);
dl_ch = memset(dl_ch, 0, sizeof(int16_t)*10);
re_offset = (re_offset+idxDC/2-2)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+idxDC/2-2) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
ch[1] = (int16_t)(((int32_t)pil[0]*rxF[1] + (int32_t)pil[1]*rxF[0])>>15);
@@ -909,7 +888,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
8);
pil += 4;
re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
ch[1] = (int16_t)(((int32_t)pil[0]*rxF[1] + (int32_t)pil[1]*rxF[0])>>15);
@@ -926,7 +905,7 @@ int nr_pdsch_channel_estimation(PHY_VARS_NR_UE *ue,
8);
pil += 4;
re_offset = (re_offset+4)&(ue->frame_parms.ofdm_symbol_size-1);
re_offset = (re_offset+4) % ue->frame_parms.ofdm_symbol_size;
rxF = (int16_t *)&rxdataF[aarx][(symbol_offset+nushift+re_offset)];
ch[0] = (int16_t)(((int32_t)pil[0]*rxF[0] - (int32_t)pil[1]*rxF[1])>>15);
ch[1] = (int16_t)(((int32_t)pil[0]*rxF[1] + (int32_t)pil[1]*rxF[0])>>15);