diff --git a/openair1/PHY/INIT/nr_init.c b/openair1/PHY/INIT/nr_init.c
index 1c29d631818ea9d6ae0ee28fd5c2ed45f85cf70f..298c69118f43fcbb83236a4d98606a09507d018b 100644
--- a/openair1/PHY/INIT/nr_init.c
+++ b/openair1/PHY/INIT/nr_init.c
@@ -67,6 +67,17 @@ int l1_north_init_gNB() {
return(0);
}
+void init_ul_delay_table(NR_DL_FRAME_PARMS *fp)
+{
+ for (int delay = -MAX_UL_DELAY_COMP; delay <= MAX_UL_DELAY_COMP; delay++) {
+ for (int k = 0; k < fp->ofdm_symbol_size; k++) {
+ double complex delay_cexp = cexp(I * (2.0 * M_PI * k * delay / fp->ofdm_symbol_size));
+ fp->ul_delay_table[MAX_UL_DELAY_COMP + delay][k].r = (int16_t)round(256 * creal(delay_cexp));
+ fp->ul_delay_table[MAX_UL_DELAY_COMP + delay][k].i = (int16_t)round(256 * cimag(delay_cexp));
+ }
+ }
+}
+
int init_codebook_gNB(PHY_VARS_gNB *gNB) {
if(gNB->frame_parms.nb_antennas_tx>1){
@@ -501,6 +512,7 @@ int phy_init_nr_gNB(PHY_VARS_gNB *gNB)
load_nrLDPClib_offload();
init_codebook_gNB(gNB);
+ init_ul_delay_table(fp);
// PBCH DMRS gold sequences generation
nr_init_pbch_dmrs(gNB);
diff --git a/openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c b/openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c
index 7827d69b7e35fa09864a88ce26785a563b21d8d8..aabdd15f4e9b96fa3485cc17ef5ee6e94ec42c47 100644
--- a/openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c
+++ b/openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c
@@ -100,6 +100,17 @@ __attribute__((always_inline)) inline c16_t c32x16cumulVectVectWithSteps(c16_t *
return c16x32div(cumul, N);
}
+int get_delay_idx(int delay) {
+ int delay_idx = MAX_UL_DELAY_COMP + delay;
+ if (delay_idx < 0) {
+ delay_idx = 0;
+ }
+ if (delay_idx > MAX_UL_DELAY_COMP<<1) {
+ delay_idx = MAX_UL_DELAY_COMP<<1;
+ }
+ return delay_idx;
+}
+
int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
unsigned char Ns,
unsigned short p,
@@ -209,9 +220,9 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
c16_t ch16 = {.r = (int16_t)ch.r, .i = (int16_t)ch.i};
*max_ch = max(*max_ch, max(abs(ch.r), abs(ch.i)));
-
- ul_ls_est[pilot_cnt << 1] = ch16;
- ul_ls_est[(pilot_cnt + 1) << 1] = ch16;
+ for (int k = pilot_cnt << 1; k < (pilot_cnt << 1) + 4; k++) {
+ ul_ls_est[k] = ch16;
+ }
pilot_cnt += 2;
}
@@ -221,6 +232,8 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
nr_est_timing_advance_pusch(&gNB->frame_parms, gNB->pusch_vars[ul_id]->ul_ch_estimates_time[aarx], &gNB->measurements.delay[ul_id]);
int delay = gNB->measurements.delay[ul_id].pusch_est_delay;
+ int delay_idx = get_delay_idx(delay);
+ c16_t *ul_delay_table = gNB->frame_parms.ul_delay_table[delay_idx];
#ifdef DEBUG_PUSCH
printf("Estimated delay = %i\n", delay >> 1);
@@ -231,21 +244,25 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
// Channel interpolation
for (int k_line = 0; k_line <= 1; k_line++) {
+
+ // Apply delay
+ int k = pilot_cnt << 1;
+ c16_t ch16 = c16mulShift(ul_ls_est[k], ul_delay_table[k], 8);
+
#ifdef DEBUG_PUSCH
re_offset = (k0 + (n << 2) + (k_line << 1)) % symbolSize;
c16_t *rxF = &rxdataF[soffset + re_offset];
- printf("pilot %4u: pil -> (%6d,%6d), rxF -> (%4d,%4d), ch -> (%4d,%4d)\n",
- pilot_cnt, pil->r, pil->i, rxF->r, rxF->i, ul_ls_est[pilot_cnt << 1].r, ul_ls_est[pilot_cnt << 1].i);
+ printf("ch -> (%4d,%4d), ch_delay_comp -> (%4d,%4d)\n", ul_ls_est[k].r, ul_ls_est[k].i, ch16.r, ch16.i);
#endif
if (pilot_cnt == 0) {
- c16multaddVectRealComplex(filt16_ul_p0, &ul_ls_est[pilot_cnt << 1], ul_ch, 16);
+ c16multaddVectRealComplex(filt16_ul_p0, &ch16, ul_ch, 16);
} else if (pilot_cnt == 1 || pilot_cnt == 2) {
- c16multaddVectRealComplex(filt16_ul_p1p2, &ul_ls_est[pilot_cnt << 1], ul_ch, 16);
+ c16multaddVectRealComplex(filt16_ul_p1p2, &ch16, ul_ch, 16);
} else if (pilot_cnt == (6 * nb_rb_pusch - 1)) {
- c16multaddVectRealComplex(filt16_ul_last, &ul_ls_est[pilot_cnt << 1], ul_ch, 16);
+ c16multaddVectRealComplex(filt16_ul_last, &ch16, ul_ch, 16);
} else {
- c16multaddVectRealComplex(filt16_ul_middle, &ul_ls_est[pilot_cnt << 1], ul_ch, 16);
+ c16multaddVectRealComplex(filt16_ul_middle, &ch16, ul_ch, 16);
if (pilot_cnt % 2 == 0) {
ul_ch += 4;
}
@@ -255,19 +272,24 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
}
}
+ // Revert delay
+ pilot_cnt = 0;
+ ul_ch = &ul_ch_estimates[p * gNB->frame_parms.nb_antennas_rx + aarx][ch_offset];
+ int inv_delay_idx = get_delay_idx(-delay);
+ c16_t *ul_inv_delay_table = gNB->frame_parms.ul_delay_table[inv_delay_idx];
+ for (int n = 0; n < 3 * nb_rb_pusch; n++) {
+ for (int k_line = 0; k_line <= 1; k_line++) {
+ int k = pilot_cnt << 1;
+ ul_ch[k] = c16mulShift(ul_ch[k], ul_inv_delay_table[k], 8);
+ ul_ch[k + 1] = c16mulShift(ul_ch[k + 1], ul_inv_delay_table[k + 1], 8);
#ifdef DEBUG_PUSCH
- ul_ch = &ul_ch_estimates[p*gNB->frame_parms.nb_antennas_rx+aarx][ch_offset];
-
- for(uint16_t idxP=0; idxP<ceil((float)nb_rb_pusch*12/8); idxP++) {
- printf("(%3d)\t",idxP);
-
- for(uint8_t idxI=0; idxI<8; idxI++) {
- printf("%d\t%d\t",ul_ch[idxP*8+idxI].r,ul_ch[idxP*8+idxI].i);
+ re_offset = (k0 + (n << 2) + (k_line << 1)) % symbolSize;
+ c16_t *rxF = &rxdataF[soffset + re_offset];
+ printf("ch -> (%4d,%4d), ch_inter -> (%4d,%4d)\n", ul_ls_est[k].r, ul_ls_est[k].i, ul_ch[k].r, ul_ch[k].i);
+#endif
+ pilot_cnt++;
}
-
- printf("\n");
}
-#endif
} else if (pusch_pdu->dmrs_config_type == pusch_dmrs_type2 && chest_freq == 0) { //pusch_dmrs_type2 |p_r,p_l,d,d,d,d,p_r,p_l,d,d,d,d|
LOG_D(PHY,"PUSCH estimation DMRS type 2, Freq-domain interpolation");
@@ -500,16 +522,15 @@ int nr_pusch_channel_estimation(PHY_VARS_gNB *gNB,
}
#ifdef DEBUG_PUSCH
- ul_ch = &ul_ch_estimates[p*gNB->frame_parms.nb_antennas_rx+aarx][ch_offset];
-
- for(int idxP=0; idxP<ceil((float)nb_rb_pusch*12/8); idxP++) {
- for(int idxI=0; idxI<8; idxI++) {
- printf("%d\t%d\t",ul_ch[idxP*8+idxI].r,ul_ch[idxP*8+idxI].i);
+ ul_ch = &ul_ch_estimates[p * gNB->frame_parms.nb_antennas_rx + aarx][ch_offset];
+ for (int idxP = 0; idxP < ceil((float)nb_rb_pusch * 12 / 8); idxP++) {
+ for (int idxI = 0; idxI < 8; idxI++) {
+ printf("%d\t%d\t", ul_ch[idxP * 8 + idxI].r, ul_ch[idxP * 8 + idxI].i);
}
-
- printf("%d\n",idxP);
+ printf("%d\n", idxP);
}
#endif
+
}
#ifdef DEBUG_CH
diff --git a/openair1/PHY/defs_nr_common.h b/openair1/PHY/defs_nr_common.h
index c99e07fe7d15412830fa52ac4a79369125af671c..b5d7bb784906fc288221b65cc6422e67322d7caa 100644
--- a/openair1/PHY/defs_nr_common.h
+++ b/openair1/PHY/defs_nr_common.h
@@ -107,6 +107,8 @@
#define NR_NB_NSCID 2
+#define MAX_UL_DELAY_COMP 20
+
extern const uint8_t nr_rv_round_map[4];
static inline
@@ -303,6 +305,8 @@ struct NR_DL_FRAME_PARMS {
/// sequence used to compensate the phase rotation due to timeshifted OFDM symbols
/// First dimenstion is for different CP lengths
c16_t timeshift_symbol_rotation[4096*2] __attribute__ ((aligned (16)));
+ /// Table used to apply the delay compensation in UL
+ c16_t ul_delay_table[2 * MAX_UL_DELAY_COMP + 1][NR_MAX_OFDM_SYMBOL_SIZE * 2];
/// shift of pilot position in one RB
uint8_t nushift;
/// SRS configuration from TS 38.331 RRC