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phy: fix CSI-RS estimation

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Changed channel estimates buffer to store RB 0 from start of buffer instead of
FFT shift offset. This simplifies channel estimation implementation. There is
also no need to add padding because each symbol/antenna start from offset 0
and/or OFDM symbol size always 32 byte aligned.

This also fixes buffer overflow detected when running UE with OCUDU gNB.
This commit is contained in:
Sakthivel Velumani
2026-04-23 03:04:39 +00:00
parent 38dc378224
commit 2c34d84d6f
1 changed files with 67 additions and 84 deletions
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openair1/PHY/NR_UE_TRANSPORT/csi_rx.c
+67 -84
View File
@@ -22,9 +22,6 @@
#include "common/utils/nr/nr_common.h"
#include "PHY/NR_UE_ESTIMATION/filt16a_32.h"
// Additional memory allocation, because of applying the filter and the memory offset to ensure memory alignment
#define FILTER_MARGIN 32
//#define NR_CSIRS_DEBUG
//#define NR_CSIIM_DEBUG
@@ -259,9 +256,8 @@ static int nr_csi_rs_channel_estimation(
const c16_t csi_rs_received_signal[][fp->samples_per_slot_wCP],
const csi_mapping_parms_t *csi_mapping,
const int CDM_group_size,
uint8_t mem_offset,
c16_t csi_rs_ls_estimated_channel[][csi_mapping->ports][fp->ofdm_symbol_size],
c16_t csi_rs_estimated_channel_freq[][csi_mapping->ports][fp->ofdm_symbol_size + FILTER_MARGIN],
c16_t csi_rs_estimated_channel_freq[][csi_mapping->ports][fp->ofdm_symbol_size],
int16_t *log2_re,
int16_t *log2_maxh,
uint32_t *noise_power)
@@ -274,12 +270,12 @@ static int nr_csi_rs_channel_estimation(
/// LS channel estimation
const uint16_t stop_rb = csirs_config_pdu->start_rb + csirs_config_pdu->nr_of_rbs;
for(uint16_t port_tx = 0; port_tx < csi_mapping->ports; port_tx++) {
memset(csi_rs_ls_estimated_channel[ant_rx][port_tx], 0, fp->ofdm_symbol_size * sizeof(c16_t));
}
for (int rb = csirs_config_pdu->start_rb; rb < (csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs); rb++) {
for (int rb = csirs_config_pdu->start_rb; rb < stop_rb; rb++) {
// for freq density 0.5 checks if even or odd RB
if(csirs_config_pdu->freq_density <= 1 && csirs_config_pdu->freq_density != (rb % 2)) {
continue;
@@ -307,8 +303,8 @@ static int nr_csi_rs_channel_estimation(
c16MulConjShift(tx_csi_rs_signal[k_tx], rx_csi_rs_signal[k_rx], nr_csi_info->csi_rs_generated_signal_bits);
// This is not just the LS estimation for each (k,l), but also the sum of the different contributions
// for the sake of optimizing the memory used.
csi_rs_ls_estimated_channel[ant_rx][port_tx][kinit_rx].r += tmp.r;
csi_rs_ls_estimated_channel[ant_rx][port_tx][kinit_rx].i += tmp.i;
csi_rs_ls_estimated_channel[ant_rx][port_tx][kinit_tx].r += tmp.r;
csi_rs_ls_estimated_channel[ant_rx][port_tx][kinit_tx].i += tmp.i;
}
}
}
@@ -341,11 +337,10 @@ static int nr_csi_rs_channel_estimation(
/// Channel interpolation
for(uint16_t port_tx = 0; port_tx < csi_mapping->ports; port_tx++) {
memset(csi_rs_estimated_channel_freq[ant_rx][port_tx], 0, (fp->ofdm_symbol_size + FILTER_MARGIN) * sizeof(c16_t));
memset(csi_rs_estimated_channel_freq[ant_rx][port_tx], 0, (fp->ofdm_symbol_size) * sizeof(c16_t));
}
for (int rb = csirs_config_pdu->start_rb; rb < (csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs); rb++) {
for (int rb = csirs_config_pdu->start_rb; rb < stop_rb; rb++) {
// for freq density 0.5 checks if even or odd RB
if(csirs_config_pdu->freq_density <= 1 && csirs_config_pdu->freq_density != (rb % 2)) {
continue;
@@ -353,15 +348,13 @@ static int nr_csi_rs_channel_estimation(
count++;
uint16_t k = (fp->first_carrier_offset + rb * NR_NB_SC_PER_RB) % fp->ofdm_symbol_size;
uint16_t k_offset = k + mem_offset;
uint16_t k = rb * NR_NB_SC_PER_RB;
for(uint16_t port_tx = 0; port_tx < csi_mapping->ports; port_tx++) {
c16_t csi_rs_ls_estimated_channel16 = csi_rs_ls_estimated_channel[ant_rx][port_tx][k];
c16_t *csi_rs_estimated_channel16 = &csi_rs_estimated_channel_freq[ant_rx][port_tx][k_offset];
if( (k == 0) || (k == fp->first_carrier_offset) ) { // Start of OFDM symbol case or first occupied subcarrier case
c16_t *csi_rs_estimated_channel16 = &csi_rs_estimated_channel_freq[ant_rx][port_tx][k];
if (k == 0) { // Start of OFDM symbol case or first occupied subcarrier case
multadd_real_vector_complex_scalar(filt24_start, csi_rs_ls_estimated_channel16, csi_rs_estimated_channel16, 24);
} else if(((k + NR_NB_SC_PER_RB) >= fp->ofdm_symbol_size) ||
(rb == (csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs-1))) { // End of OFDM symbol case or Last occupied subcarrier case
} else if (rb == (stop_rb - 1)) { // End of OFDM symbol case or Last occupied subcarrier case
multadd_real_vector_complex_scalar(filt24_end, csi_rs_ls_estimated_channel16, csi_rs_estimated_channel16 - 12, 24);
} else { // Middle case
multadd_real_vector_complex_scalar(filt24_middle, csi_rs_ls_estimated_channel16, csi_rs_estimated_channel16 - 12, 24);
@@ -373,15 +366,14 @@ static int nr_csi_rs_channel_estimation(
AssertFatal(csirs_config_pdu->nr_of_rbs > 0, " nr_of_rbs needs to be greater than 0\n");
uint16_t noise_real[fp->nb_antennas_rx][csi_mapping->ports][csirs_config_pdu->nr_of_rbs];
uint16_t noise_imag[fp->nb_antennas_rx][csi_mapping->ports][csirs_config_pdu->nr_of_rbs];
for (int rb = csirs_config_pdu->start_rb; rb < (csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs); rb++) {
for (int rb = csirs_config_pdu->start_rb; rb < stop_rb; rb++) {
if (csirs_config_pdu->freq_density <= 1 && csirs_config_pdu->freq_density != (rb % 2)) {
continue;
}
uint16_t k = (fp->first_carrier_offset + rb*NR_NB_SC_PER_RB) % fp->ofdm_symbol_size;
uint16_t k_offset = k + mem_offset;
uint16_t k = rb * NR_NB_SC_PER_RB;
for(uint16_t port_tx = 0; port_tx < csi_mapping->ports; port_tx++) {
c16_t *csi_rs_ls_estimated_channel16 = &csi_rs_ls_estimated_channel[ant_rx][port_tx][k];
c16_t *csi_rs_estimated_channel16 = &csi_rs_estimated_channel_freq[ant_rx][port_tx][k_offset];
c16_t *csi_rs_estimated_channel16 = &csi_rs_estimated_channel_freq[ant_rx][port_tx][k];
noise_real[ant_rx][port_tx][rb-csirs_config_pdu->start_rb] = abs(csi_rs_ls_estimated_channel16->r-csi_rs_estimated_channel16->r);
noise_imag[ant_rx][port_tx][rb-csirs_config_pdu->start_rb] = abs(csi_rs_ls_estimated_channel16->i-csi_rs_estimated_channel16->i);
maxh = cmax3(maxh, abs(csi_rs_estimated_channel16->r), abs(csi_rs_estimated_channel16->i));
@@ -393,19 +385,20 @@ static int nr_csi_rs_channel_estimation(
#ifdef NR_CSIRS_DEBUG
for(int k = 0; k < fp->ofdm_symbol_size; k++) {
int rb = k >= fp->first_carrier_offset ?
(k - fp->first_carrier_offset)/NR_NB_SC_PER_RB :
(k + fp->ofdm_symbol_size - fp->first_carrier_offset)/NR_NB_SC_PER_RB;
int rb = k / NR_NB_SC_PER_RB;
LOG_I(NR_PHY, "(k = %4d) |\t", k);
for(uint16_t port_tx = 0; port_tx < csi_mapping->ports; port_tx++) {
c16_t *csi_rs_ls_estimated_channel16 = &csi_rs_ls_estimated_channel[ant_rx][port_tx][0];
c16_t *csi_rs_estimated_channel16 = &csi_rs_estimated_channel_freq[ant_rx][port_tx][mem_offset];
c16_t *csi_rs_estimated_channel16 = &csi_rs_estimated_channel_freq[ant_rx][port_tx][0];
printf("Channel port_tx %d --> ant_rx %d : ls (%4d,%4d), int (%4d,%4d), noise (%4d,%4d) | ",
port_tx+3000, ant_rx,
csi_rs_ls_estimated_channel16[k].r, csi_rs_ls_estimated_channel16[k].i,
csi_rs_estimated_channel16[k].r, csi_rs_estimated_channel16[k].i,
rb >= csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs ? 0 : noise_real[ant_rx][port_tx][rb-csirs_config_pdu->start_rb],
rb >= csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs ? 0 : noise_imag[ant_rx][port_tx][rb-csirs_config_pdu->start_rb]);
port_tx + 3000,
ant_rx,
csi_rs_ls_estimated_channel16[k].r,
csi_rs_ls_estimated_channel16[k].i,
csi_rs_estimated_channel16[k].r,
csi_rs_estimated_channel16[k].i,
rb >= stop_rb ? 0 : noise_real[ant_rx][port_tx][rb - csirs_config_pdu->start_rb],
rb >= stop_rb ? 0 : noise_imag[ant_rx][port_tx][rb - csirs_config_pdu->start_rb]);
}
printf("\n");
}
@@ -426,8 +419,7 @@ static int nr_csi_rs_channel_estimation(
static int nr_csi_rs_ri_estimation(const PHY_VARS_NR_UE *ue,
const fapi_nr_dl_config_csirs_pdu_rel15_t *csirs_config_pdu,
const uint8_t N_ports,
uint8_t mem_offset,
c16_t csi_rs_estimated_channel_freq[][N_ports][ue->frame_parms.ofdm_symbol_size + FILTER_MARGIN],
c16_t csi_rs_estimated_channel_freq[][N_ports][ue->frame_parms.ofdm_symbol_size],
const int16_t log2_maxh,
uint8_t *rank_indicator)
{
@@ -450,11 +442,11 @@ static int nr_csi_rs_ri_estimation(const PHY_VARS_NR_UE *ue,
*/
c16_t csi_rs_estimated_conjch_ch[frame_parms->nb_antennas_rx][N_ports][frame_parms->nb_antennas_rx][N_ports]
[frame_parms->ofdm_symbol_size + FILTER_MARGIN] __attribute__((aligned(32)));
int32_t csi_rs_estimated_A_MF[N_ports][N_ports][frame_parms->ofdm_symbol_size + FILTER_MARGIN] __attribute__((aligned(32)));
int32_t csi_rs_estimated_A_MF_sq[N_ports][N_ports][frame_parms->ofdm_symbol_size + FILTER_MARGIN] __attribute__((aligned(32)));
int32_t csi_rs_estimated_determ_fin[frame_parms->ofdm_symbol_size + FILTER_MARGIN] __attribute__((aligned(32)));
int32_t csi_rs_estimated_numer_fin[frame_parms->ofdm_symbol_size + FILTER_MARGIN] __attribute__((aligned(32)));
[frame_parms->ofdm_symbol_size] __attribute__((aligned(32)));
int32_t csi_rs_estimated_A_MF[N_ports][N_ports][frame_parms->ofdm_symbol_size] __attribute__((aligned(32)));
int32_t csi_rs_estimated_A_MF_sq[N_ports][N_ports][frame_parms->ofdm_symbol_size] __attribute__((aligned(32)));
int32_t csi_rs_estimated_determ_fin[frame_parms->ofdm_symbol_size] __attribute__((aligned(32)));
int32_t csi_rs_estimated_numer_fin[frame_parms->ofdm_symbol_size] __attribute__((aligned(32)));
const uint8_t sum_shift = 1; // log2(2x2) = 2, which is a shift of 1 bit
for (int rb = csirs_config_pdu->start_rb; rb < (csirs_config_pdu->start_rb+csirs_config_pdu->nr_of_rbs); rb++) {
@@ -462,8 +454,7 @@ static int nr_csi_rs_ri_estimation(const PHY_VARS_NR_UE *ue,
if (csirs_config_pdu->freq_density <= 1 && csirs_config_pdu->freq_density != (rb % 2)) {
continue;
}
uint16_t k = (frame_parms->first_carrier_offset + rb*NR_NB_SC_PER_RB) % frame_parms->ofdm_symbol_size;
uint16_t k_offset = k + mem_offset;
uint16_t k = rb * NR_NB_SC_PER_RB;
for (int ant_rx_conjch = 0; ant_rx_conjch < frame_parms->nb_antennas_rx; ant_rx_conjch++) {
for(uint16_t port_tx_conjch = 0; port_tx_conjch < N_ports; port_tx_conjch++) {
@@ -471,16 +462,17 @@ static int nr_csi_rs_ri_estimation(const PHY_VARS_NR_UE *ue,
for(uint16_t port_tx_ch = 0; port_tx_ch < N_ports; port_tx_ch++) {
// conjch x ch computation
nr_conjch0_mult_ch1(&csi_rs_estimated_channel_freq[ant_rx_conjch][port_tx_conjch][k_offset],
&csi_rs_estimated_channel_freq[ant_rx_ch][port_tx_ch][k_offset],
&csi_rs_estimated_conjch_ch[ant_rx_conjch][port_tx_conjch][ant_rx_ch][port_tx_ch][k_offset],
nr_conjch0_mult_ch1(&csi_rs_estimated_channel_freq[ant_rx_conjch][port_tx_conjch][k],
&csi_rs_estimated_channel_freq[ant_rx_ch][port_tx_ch][k],
&csi_rs_estimated_conjch_ch[ant_rx_conjch][port_tx_conjch][ant_rx_ch][port_tx_ch][k],
1,
log2_maxh);
// construct Hh x H elements
if(ant_rx_conjch == ant_rx_ch) {
nr_a_sum_b(
(c16_t *)&csi_rs_estimated_A_MF[port_tx_conjch][port_tx_ch][k_offset], (c16_t *)&csi_rs_estimated_conjch_ch[ant_rx_conjch][port_tx_conjch][ant_rx_ch][port_tx_ch][k_offset], 1);
nr_a_sum_b((c16_t *)&csi_rs_estimated_A_MF[port_tx_conjch][port_tx_ch][k],
(c16_t *)&csi_rs_estimated_conjch_ch[ant_rx_conjch][port_tx_conjch][ant_rx_ch][port_tx_ch][k],
1);
}
}
}
@@ -488,44 +480,44 @@ static int nr_csi_rs_ri_estimation(const PHY_VARS_NR_UE *ue,
}
// compute the determinant of A_MF (denominator)
nr_det_A_MF_2x2(&csi_rs_estimated_A_MF[0][0][k_offset],
&csi_rs_estimated_A_MF[0][1][k_offset],
&csi_rs_estimated_A_MF[1][0][k_offset],
&csi_rs_estimated_A_MF[1][1][k_offset],
&csi_rs_estimated_determ_fin[k_offset],
nr_det_A_MF_2x2(&csi_rs_estimated_A_MF[0][0][k],
&csi_rs_estimated_A_MF[0][1][k],
&csi_rs_estimated_A_MF[1][0][k],
&csi_rs_estimated_A_MF[1][1][k],
&csi_rs_estimated_determ_fin[k],
1);
// compute the square of A_MF (numerator)
nr_squared_matrix_element(&csi_rs_estimated_A_MF[0][0][k_offset], &csi_rs_estimated_A_MF_sq[0][0][k_offset], 1);
nr_squared_matrix_element(&csi_rs_estimated_A_MF[0][1][k_offset], &csi_rs_estimated_A_MF_sq[0][1][k_offset], 1);
nr_squared_matrix_element(&csi_rs_estimated_A_MF[1][0][k_offset], &csi_rs_estimated_A_MF_sq[1][0][k_offset], 1);
nr_squared_matrix_element(&csi_rs_estimated_A_MF[1][1][k_offset], &csi_rs_estimated_A_MF_sq[1][1][k_offset], 1);
nr_numer_2x2(&csi_rs_estimated_A_MF_sq[0][0][k_offset],
&csi_rs_estimated_A_MF_sq[0][1][k_offset],
&csi_rs_estimated_A_MF_sq[1][0][k_offset],
&csi_rs_estimated_A_MF_sq[1][1][k_offset],
&csi_rs_estimated_numer_fin[k_offset],
nr_squared_matrix_element(&csi_rs_estimated_A_MF[0][0][k], &csi_rs_estimated_A_MF_sq[0][0][k], 1);
nr_squared_matrix_element(&csi_rs_estimated_A_MF[0][1][k], &csi_rs_estimated_A_MF_sq[0][1][k], 1);
nr_squared_matrix_element(&csi_rs_estimated_A_MF[1][0][k], &csi_rs_estimated_A_MF_sq[1][0][k], 1);
nr_squared_matrix_element(&csi_rs_estimated_A_MF[1][1][k], &csi_rs_estimated_A_MF_sq[1][1][k], 1);
nr_numer_2x2(&csi_rs_estimated_A_MF_sq[0][0][k],
&csi_rs_estimated_A_MF_sq[0][1][k],
&csi_rs_estimated_A_MF_sq[1][0][k],
&csi_rs_estimated_A_MF_sq[1][1][k],
&csi_rs_estimated_numer_fin[k],
1);
#ifdef NR_CSIRS_DEBUG
for(uint16_t port_tx_conjch = 0; port_tx_conjch < N_ports; port_tx_conjch++) {
for(uint16_t port_tx_ch = 0; port_tx_ch < N_ports; port_tx_ch++) {
c16_t *csi_rs_estimated_A_MF_k = (c16_t *) &csi_rs_estimated_A_MF[port_tx_conjch][port_tx_ch][k_offset];
c16_t *csi_rs_estimated_A_MF_k = (c16_t *)&csi_rs_estimated_A_MF[port_tx_conjch][port_tx_ch][k];
LOG_I(NR_PHY, "(%i) csi_rs_estimated_A_MF[%i][%i] = (%i, %i)\n",
k, port_tx_conjch, port_tx_ch, csi_rs_estimated_A_MF_k->r, csi_rs_estimated_A_MF_k->i);
c16_t *csi_rs_estimated_A_MF_sq_k = (c16_t *) &csi_rs_estimated_A_MF_sq[port_tx_conjch][port_tx_ch][k_offset];
c16_t *csi_rs_estimated_A_MF_sq_k = (c16_t *)&csi_rs_estimated_A_MF_sq[port_tx_conjch][port_tx_ch][k];
LOG_I(NR_PHY, "(%i) csi_rs_estimated_A_MF_sq[%i][%i] = (%i, %i)\n",
k, port_tx_conjch, port_tx_ch, csi_rs_estimated_A_MF_sq_k->r, csi_rs_estimated_A_MF_sq_k->i);
}
}
LOG_I(NR_PHY, "(%i) csi_rs_estimated_determ_fin = %i\n", k, csi_rs_estimated_determ_fin[k_offset]);
LOG_I(NR_PHY, "(%i) csi_rs_estimated_numer_fin = %i\n", k, csi_rs_estimated_numer_fin[k_offset]>>sum_shift);
LOG_I(NR_PHY, "(%i) csi_rs_estimated_determ_fin = %i\n", k, csi_rs_estimated_determ_fin[k]);
LOG_I(NR_PHY, "(%i) csi_rs_estimated_numer_fin = %i\n", k, csi_rs_estimated_numer_fin[k] >> sum_shift);
#endif
// compute the conditional number
for (int sc_idx=0; sc_idx < NR_NB_SC_PER_RB; sc_idx++) {
int8_t csi_rs_estimated_denum_db = dB_fixed(csi_rs_estimated_determ_fin[k_offset + sc_idx]);
int8_t csi_rs_estimated_numer_db = dB_fixed(csi_rs_estimated_numer_fin[k_offset + sc_idx]>>sum_shift);
int8_t csi_rs_estimated_denum_db = dB_fixed(csi_rs_estimated_determ_fin[k + sc_idx]);
int8_t csi_rs_estimated_numer_db = dB_fixed(csi_rs_estimated_numer_fin[k + sc_idx] >> sum_shift);
int8_t cond_db = csi_rs_estimated_numer_db - csi_rs_estimated_denum_db;
#ifdef NR_CSIRS_DEBUG
@@ -558,8 +550,7 @@ static int nr_csi_rs_ri_estimation(const PHY_VARS_NR_UE *ue,
static int nr_csi_rs_pmi_estimation(const PHY_VARS_NR_UE *ue,
const fapi_nr_dl_config_csirs_pdu_rel15_t *csirs_config_pdu,
const uint8_t N_ports,
uint8_t mem_offset,
const c16_t csi_rs_estimated_channel_freq[][N_ports][ue->frame_parms.ofdm_symbol_size + FILTER_MARGIN],
const c16_t csi_rs_estimated_channel_freq[][N_ports][ue->frame_parms.ofdm_symbol_size],
const uint32_t interference_plus_noise_power,
const uint8_t rank_indicator,
const int16_t log2_re,
@@ -586,10 +577,9 @@ static int nr_csi_rs_pmi_estimation(const PHY_VARS_NR_UE *ue,
if (csirs_config_pdu->freq_density <= 1 && csirs_config_pdu->freq_density != (rb % 2)) {
continue;
}
uint16_t k = (frame_parms->first_carrier_offset + rb * NR_NB_SC_PER_RB) % frame_parms->ofdm_symbol_size;
uint16_t k_offset = k + mem_offset;
uint16_t k = rb * NR_NB_SC_PER_RB;
const c16_t h = csi_rs_estimated_channel_freq[0][0][k_offset];
const c16_t h = csi_rs_estimated_channel_freq[0][0][k];
signal_power += (int64_t)h.r * h.r + (int64_t)h.i * h.i;
count++;
}
@@ -614,11 +604,10 @@ static int nr_csi_rs_pmi_estimation(const PHY_VARS_NR_UE *ue,
if (csirs_config_pdu->freq_density <= 1 && csirs_config_pdu->freq_density != (rb % 2)) {
continue;
}
uint16_t k = (frame_parms->first_carrier_offset + rb * NR_NB_SC_PER_RB) % frame_parms->ofdm_symbol_size;
uint16_t k_offset = k + mem_offset;
uint16_t k = rb * NR_NB_SC_PER_RB;
for (int ant_rx = 0; ant_rx < frame_parms->nb_antennas_rx; ant_rx++) {
const c16_t p0 = csi_rs_estimated_channel_freq[ant_rx][0][k_offset];
const c16_t p1 = csi_rs_estimated_channel_freq[ant_rx][1][k_offset];
const c16_t p0 = csi_rs_estimated_channel_freq[ant_rx][0][k];
const c16_t p1 = csi_rs_estimated_channel_freq[ant_rx][1][k];
// H_p0 + 1*H_p1 = (H_p0_re + H_p1_re) + 1j*(H_p0_im + H_p1_im)
sum[0].r += (p0.r + p1.r);
@@ -860,15 +849,12 @@ void nr_ue_csi_rs_procedures(PHY_VARS_NR_UE *ue,
csi_info->csi_rs_generated_signal_bits = log2_approx(AMP);
/* OFDM symbol size \times sizeof(c16_t) is always multiple of 64. Since the
estimates have first RB at start of buffer we don't need padding for 32 or 64
byte alignment. */
c16_t csi_rs_ls_estimated_channel[frame_parms->nb_antennas_rx][mapping_parms.ports][frame_parms->ofdm_symbol_size];
c16_t csi_rs_estimated_channel_freq[frame_parms->nb_antennas_rx][mapping_parms.ports]
[frame_parms->ofdm_symbol_size + FILTER_MARGIN];
c16_t csi_rs_estimated_channel_freq[frame_parms->nb_antennas_rx][mapping_parms.ports][frame_parms->ofdm_symbol_size];
// (long)&csi_rs_estimated_channel_freq[0][0][frame_parms->first_carrier_offset] & 0x1F
// gives us the remainder of the integer division by 32 of the memory address
// By subtracting the previous value of 32, we know how much is left to have a multiple of 32.
// Doing >> 2 <=> /sizeof(int32_t), we know what is the index offset of the array.
uint8_t mem_offset = (((32 - ((long)&csi_rs_estimated_channel_freq[0][0][frame_parms->first_carrier_offset])) & 0x1F) >> 2);
int CDM_group_size = get_cdm_group_size(csirs_config_pdu->cdm_type);
c16_t csi_rs_received_signal[frame_parms->nb_antennas_rx][frame_parms->samples_per_slot_wCP];
uint32_t rsrp = 0;
@@ -902,7 +888,6 @@ void nr_ue_csi_rs_procedures(PHY_VARS_NR_UE *ue,
csi_rs_received_signal,
&mapping_parms,
CDM_group_size,
mem_offset,
csi_rs_ls_estimated_channel,
csi_rs_estimated_channel_freq,
&log2_re,
@@ -915,7 +900,6 @@ void nr_ue_csi_rs_procedures(PHY_VARS_NR_UE *ue,
nr_csi_rs_ri_estimation(ue,
csirs_config_pdu,
mapping_parms.ports,
mem_offset,
csi_rs_estimated_channel_freq,
log2_maxh,
&rank_indicator);
@@ -930,7 +914,6 @@ void nr_ue_csi_rs_procedures(PHY_VARS_NR_UE *ue,
nr_csi_rs_pmi_estimation(ue,
csirs_config_pdu,
mapping_parms.ports,
mem_offset,
csi_rs_estimated_channel_freq,
csi_info->csi_im_meas_computed ? csi_info->interference_plus_noise_power : noise_power,
rank_indicator,