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initial commit of gNB prach processing

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This commit is contained in:
Raymond Knopp
2019-05-14 11:42:17 +02:00
parent 2da6fb8efb
commit f71c2e0830
1 changed files with 674 additions and 0 deletions
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openair1/PHY/NR_TRANSPORT/nr_prach.c
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/*
* Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The OpenAirInterface Software Alliance licenses this file to You under
* the OAI Public License, Version 1.1 (the "License"); you may not use this file
* except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.openairinterface.org/?page_id=698
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*-------------------------------------------------------------------------------
* For more information about the OpenAirInterface (OAI) Software Alliance:
* contact@openairinterface.org
*/
/*! \file PHY/NR_TRANSPORT/nr_prach.c
* \brief Top-level routines for generating and decoding the PRACH physical channel V15.4 2018-12
* \author R. Knopp
* \date 2019
* \version 0.1
* \company Eurecom
* \email: knopp@eurecom.fr
* \note
* \warning
*/
void rx_nr_prach(PHY_VARS_gNB *gNB,
RU_t *ru,
uint16_t *max_preamble,
uint16_t *max_preamble_energy,
uint16_t *max_preamble_delay,
uint16_t Nf,
uint8_t tdd_mapindex
)
{
int i;
NR_DL_FRAME_PARMS *fp;
lte_frame_type_t frame_type;
uint16_t rootSequenceIndex;
uint8_t prach_ConfigIndex;
uint8_t Ncs_config;
uint8_t restricted_set;
uint8_t n_ra_prb;
int subframe;
int16_t *prachF=NULL;
int16_t **rxsigF=NULL;
int nb_rx;
int16_t *prach2;
uint8_t preamble_index;
uint16_t NCS,NCS2;
uint16_t preamble_offset=0,preamble_offset_old;
int16_t preamble_shift=0;
uint32_t preamble_shift2;
uint16_t preamble_index0=0,n_shift_ra=0,n_shift_ra_bar;
uint16_t d_start=0;
uint16_t numshift=0;
uint16_t *prach_root_sequence_map;
uint8_t not_found;
int k=0;
uint16_t u;
int16_t *Xu=0;
uint16_t offset;
int16_t Ncp;
uint16_t first_nonzero_root_idx=0;
uint8_t new_dft=0;
uint8_t aa;
int32_t lev;
int16_t levdB;
int fft_size,log2_ifft_size;
int16_t prach_ifft_tmp[2048*2] __attribute__((aligned(32)));
int32_t *prach_ifft=(int32_t*)NULL;
int32_t **prach_ifftp=(int32_t **)NULL;
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
int prach_ifft_cnt=0;
#endif
if (ru) {
fp = ru->frame_parms;
nb_rx = ru->nb_rx;
}
else if (gNB) {
fp = &gNB->frame_parms;
nb_rx = fp->nb_antennas_rx;
}
else AssertFatal(1==0,"rx_prach called without valid RU or gNB descriptor\n");
frame_type = fp->frame_type;
rootSequenceIndex = fp->prach_config_common.rootSequenceIndex;
prach_ConfigIndex = fp->prach_config_common.prach_ConfigInfo.prach_ConfigIndex;
Ncs_config = fp->prach_config_common.prach_ConfigInfo.zeroCorrelationZoneConfig;
restricted_set = fp->prach_config_common.prach_ConfigInfo.highSpeedFlag;
n_ra_prb = get_prach_prb_offset(fp,prach_ConfigIndex,
fp->prach_config_common.prach_ConfigInfo.prach_FreqOffset,
tdd_mapindex,Nf);
int16_t *prach[nb_rx];
uint8_t prach_fmt = get_prach_fmt(prach_ConfigIndex,frame_type);
uint16_t N_ZC = (prach_fmt <4)?839:139;
if (gNB) {
prach_ifftp = gNB->prach_vars.prach_ifft[0];
subframe = gNB->proc.subframe_prach;
prachF = gNB->prach_vars.prachF;
rxsigF = gNB->prach_vars.rxsigF[0];
if (LOG_DEBUGFLAG(PRACH)){
if (((ru->proc.frame_prach)&1023) < 20) LOG_I(PHY,"PRACH (gNB) : running rx_prach for subframe %d, prach_FreqOffset %d, prach_ConfigIndex %d , rootSequenceIndex %d\n", subframe,fp->prach_config_common.prach_ConfigInfo.prach_FreqOffset,prach_ConfigIndex,rootSequenceIndex);
}
}
else {
subframe = ru->proc.subframe_prach;
rxsigF = ru->prach_rxsigF;
if (LOG_DEBUGFLAG(PRACH)){
if (((ru->proc.frame_prach)&1023) < 20) LOG_I(PHY,"PRACH (RU) : running rx_prach for subframe %d, prach_FreqOffset %d, prach_ConfigIndex %d\n",
subframe,fp->prach_config_common.prach_ConfigInfo.prach_FreqOffset,prach_ConfigIndex);
}
}
AssertFatal(ru!=NULL,"ru is null\n");
for (aa=0; aa<nb_rx; aa++) {
if (ru->if_south == LOCAL_RF) { // set the time-domain signal if we have to use it in this node
// DJP - indexing below in subframe zero takes us off the beginning of the array???
prach[aa] = (int16_t*)&ru->common.rxdata[aa][(subframe*fp->samples_per_tti)-ru->N_TA_offset];
if (LOG_DUMPFLAG(PRACH)){
int32_t en0=signal_energy((int32_t*)prach[aa],fp->samples_per_tti);
int8_t dbEn0 = dB_fixed(en0);
int8_t rach_dBm = dbEn0 - ru->rx_total_gain_dB;
char buffer[80];
if (dbEn0>32 && prach[0]!= NULL) {
static int counter=0;
sprintf(buffer, "%s%d", "/tmp/prach_rx",counter);
LOG_M(buffer,"prach_rx",prach[0],fp->samples_per_tti,1,13);
}
if (dB_fixed(en0)>32) {
sprintf(buffer, "rach_dBm:%d",rach_dBm);
if (prach[0]!= NULL) LOG_M("prach_rx","prach_rx",prach[0],fp->samples_per_tti,1,1);
LOG_I(PHY,"RU %d, br_flag %d ce_level %d frame %d subframe %d per_tti:%d prach:%p (energy %d) TA:%d %s rxdata:%p index:%d\n",
ru->idx,br_flag,ce_level,ru->proc.frame_prach,subframe,fp->samples_per_tti,
prach[aa],dbEn0,ru->N_TA_offset,buffer,ru->common.rxdata[aa],
(subframe*fp->samples_per_tti)-ru->N_TA_offset);
}
}
}
}
// First compute physical root sequence
if (restricted_set == 0) {
AssertFatal(Ncs_config<=15,
"Illegal Ncs_config for unrestricted format %d\n",Ncs_config);
NCS = NCS_unrestricted[Ncs_config];
} else {
AssertFatal(Ncs_config<=14,
"FATAL, Illegal Ncs_config for restricted format %d\n",Ncs_config);
NCS = NCS_restricted[Ncs_config];
}
if (gNB) start_meas(&gNB->rx_prach);
prach_root_sequence_map = (prach_fmt < 4) ? prach_root_sequence_map0_3 : prach_root_sequence_map4;
// PDP is oversampled, e.g. 1024 sample instead of 839
// Adapt the NCS (zero-correlation zones) with oversampling factor e.g. 1024/839
NCS2 = (N_ZC==839) ? ((NCS<<10)/839) : ((NCS<<8)/139);
if (NCS2==0)
NCS2 = N_ZC;
switch (prach_fmt) {
case 0:
Ncp = 3168;
break;
case 1:
Ncp = 21024;
break;
case 2:
Ncp = 4688;
break;
case 3:
Ncp = 3168;
break;
case 0xa1:
Ncp = 288/(1<<mu);
break;
case 0xa2:
Ncp = 576/(1<<mu);
break;
case 0xa3:
Ncp = 864/(1<<mu);
break;
case 0xb1:
Ncp = 216/(1<<mu);
break;
case 0xb2:
Ncp = 360/(1<<mu);
break;
case 0xb3:
Ncp = 504/(1<<mu);
break;
case 0xb4:
Ncp = 936/(1<<mu);
break;
case 0xc0:
Ncp = 1240/(1<<mu);
break;
case 0xc2:
Ncp = 2048/(1<<mu);
break;
default:
Ncp = 3168;
break;
}
// Note: Assumes PUSCH SCS @ 30 kHz, take values for formats 0-2 and adjust for others below
int kbar = 1;
int K = 24;
if (prach_fmt == 3) {
K=4;
kbar=10;
}
else if (prach_fmt > 3) {
// Note: Assumes that PRACH SCS is same as PUSCH SCS
K=1;
kbar=2;
}
if (((gNB!=NULL) && (ru->function != NGFI_RAU_IF4p5))||
((gNB==NULL) && (ru->function == NGFI_RRU_IF4p5))) { // compute the DFTs of the PRACH temporal resources
// Do forward transform
if (LOG_DEBUGFLAG(PRACH)) {
LOG_D(PHY,"rx_prach: Doing FFT for N_RB_UL %d nb_rx:%d Ncp:%d\n",fp->N_RB_UL, nb_rx, Ncp);
}
for (aa=0; aa<nb_rx; aa++) {
AssertFatal(prach[aa]!=NULL,"prach[%d] is null\n",aa);
prach2 = prach[aa] + (Ncp<<1);
// do DFT
switch (fp->N_RB_UL) {
case 6:
case 15:
case 25:
case 50:
case 75:
case 100:
AssertFatal(1==0,"N_RB_UL %d not support for NR PRACH yet\n",fp->N_RB_UL);
break;
case 106:
case 136:
if (fp->threequarter_fs==0) {
//40 MHz @ 61.44 Ms/s
//50 MHz @ 61.44 Ms/s
if (prach_fmt == 0 || prach_fmt == 1 || prach_fmt == 2)
dft24576(prach2,rxsigF[aa],1);
if (prach_fmt == 1 || prach_fmt == 2)
dft24576(prach2+49152,rxsigF[aa]+49152,1);
if (prach_fmt == 2) {
dft24576(prach2+(49152*2),rxsigF[aa]+(49152*2),1);
dft24576(prach2+(49152*3),rxsigF[aa]+(49152*3),1);
}
if (prach_fmt == 3)
for (int i=0;i<4;i++) dft6144(prach2+(i*12288),rxsigF[aa]+(i*12288),1);
if (prach_fmt >3) {
dft2048(prach2,rxsigF[aa],1);
if (prach_fmt != 0xc0) dft2048(prach2+4096,rxsigF[aa]+4096,1);
}
if (prach_fmt == 0xa2 || prach_fmt == 0xa3 || prach_fmt == 0xb2 || prach_fmt == 0xb3 || prach_fmt == 0xb4 || prach_fmt == 0xc2) {
dft2048(prach2+4096*2,rxsigF[aa]+4096*2,1);
dft2048(prach2+4096*3,rxsigF[aa]+4096*3,1);
}
if (prach_fmt == 0xa3 || prach_fmt == 0xb3 || prach_fmt == 0xc2) {
dft2048(prach2+4096*4,rxsigF[aa]+4096*4,1);
dft2048(prach2+4096*5,rxsigF[aa]+4096*5,1);
}
if (prach_fmt == 0xc2)
for (int i=6;i<11;i++) dft2048(prach2+(3072*i),rxsigF[aa]+(3072*i),1);
} else {
// 40 MHz @ 46.08 Ms/s
AssertFatal(fp->N_RB_UL == 106,"cannot do 136 PRBs with 3/4 sampling\n");
if (prach_fmt == 0 || prach_fmt == 1 || prach_fmt == 2)
dft18432(prach2,rxsigF[aa],1);
if (prach_fmt == 1 || prach_fmt == 2)
dft18432(prach2+36864,rxsigF[aa]+36864,1);
if (prach_fmt == 3)
dft18432(prach2+(2*36864),rxsigF[aa]+(2*36864),1);
if (prach_fmt >3) {
dft1536(prach2,rxsigF[aa],1);
if (prach_fmt != 0xc0) dft1536(prach2+3072,rxsigF[aa]+3072,1);
}
if (prach_fmt == 0xa2 || prach_fmt == 0xa3 || prach_fmt == 0xb2 || prach_fmt == 0xb3 || prach_fmt == 0xb4 || prach_fmt == 0xc2) {
dft1536(prach2+3072*2,rxsigF[aa]+3072*2,1);
dft1536(prach2+3072*3,rxsigF[aa]+3072*3,1);
}
if (prach_fmt == 0xa3 || prach_fmt == 0xb3 || prach_fmt == c2) {
dft1536(prach2+3072*4,rxsigF[aa]+3072*4,1);
dft1536(prach2+3072*5,rxsigF[aa]+3072*5,1);
}
if (prach_fmt == 0xc2)
for (int i=6;i<11;i++) dft1536(prach2+(3072*i),rxsigF[aa]+(3072*i),1);
}
break;
case 216:
case 246:
case 272:
if (fp->threequarter_fs==0) {
//80,90,100 MHz @ 61.44 Ms/s
if (prach_fmt == 0 || prach_fmt == 1 || prach_fmt == 2)
dft49152(prach2,rxsigF[aa],1);
if (prach_fmt == 1 || prach_fmt == 2)
dft49152(prach2+98304,rxsigF[aa]+98304,1);
if (prach_fmt == 3)
dft49152(prach2+(2*98304),rxsigF[aa]+(2*98304),1);
if (prach_fmt >3) {
dft4096(prach2,rxsigF[aa],1);
if (prach_fmt != 0xc0) dft4096(prach2+8192,rxsigF[aa]+8192,1);
}
if (prach_fmt == 0xa2 || prach_fmt == 0xa3 || prach_fmt == 0xb2 || prach_fmt == 0xb3 || prach_fmt == 0xb4 || prach_fmt == 0xc2) {
dft4096(prach2+8192*2,rxsigF[aa]+8192*2,1);
dft4096(prach2+8192*3,rxsigF[aa]+8192*3,1);
}
if (prach_fmt == 0xa3 || prach_fmt == 0xb3 || prach_fmt == c2) {
dft4096(prach2+8192*4,rxsigF[aa]+8192*4,1);
dft4096(prach2+8192*5,rxsigF[aa]+8192*5,1);
}
if (prach_fmt == 0xc2)
for (int i=6;i<11;i++) dft4096(prach2+(8192*i),rxsigF[aa]+(8192*i),1);
} else {
AssertFatal(fp->N_RB_UL == 216,"cannot do 136 PRBs with 3/4 sampling\n");
// 80 MHz @ 46.08 Ms/s
AssertFatal(fp->N_RB_UL == 136,"cannot do 136 PRBs with 3/4 sampling\n");
if (prach_fmt == 0 || prach_fmt == 1 || prach_fmt == 2)
dft36864(prach2,rxsigF[aa],1);
if (prach_fmt == 1 || prach_fmt == 2)
dft36864(prach2+73728,rxsigF[aa]+73728,1);
if (prach_fmt == 3)
dft36864(prach2+(2*73728),rxsigF[aa]+(2*73728),1);
if (prach_fmt >3) {
dft3072(prach2,rxsigF[aa],1);
if (prach_fmt != 0xc0) dft3072(prach2+6144,rxsigF[aa]+6144,1);
}
if (prach_fmt == 0xa2 || prach_fmt == 0xa3 || prach_fmt == 0xb2 || prach_fmt == 0xb3 || prach_fmt == 0xb4 || prach_fmt == 0xc2) {
dft3072(prach2+6144*2,rxsigF[aa]+6144*2,1);
dft3072(prach2+6144*3,rxsigF[aa]+6144*3,1);
}
if (prach_fmt == 0xa3 || prach_fmt == 0xb3 || prach_fmt == c2) {
dft3072(prach2+6144*4,rxsigF[aa]+6144*4,1);
dft3072(prach2+6144*5,rxsigF[aa]+6144*5,1);
}
if (prach_fmt == 0xc2)
for (int i=6;i<11;i++) dft3072(prach2+(6144*i),rxsigF[aa]+(6144*i),1);
}
break;
}
k = (12*n_ra_prb) - 6*fp->N_RB_UL;
if (k<0) {
k+=(fp->ofdm_symbol_size);
}
k*=K;
k+=kbar;
k*=2;
int dftsize_x2 = fp->ofdm_symbol_size*24;
//LOG_D(PHY,"Shifting prach_rxF from %d to 0\n",k);
if ((k+(839*2)) > dftsize_x2) { // PRACH signal is split around DC
memmove((void*)&rxsigF[aa][dftsize_x2-k],(void*)&rxsigF[aa][0],(k+(839*2)-dftsize_x2)*2);
memmove((void*)&rxsigF[aa][0],(void*)(&rxsigF[aa][k]),(dftsize_x2-k)*2);
}
else // PRACH signal is not split around DC
memmove((void*)&rxsigF[aa][0],(void*)(&rxsigF[aa][k]),839*4);
}
}
if ((eNB==NULL) && (ru!=NULL) && ru->function == NGFI_RRU_IF4p5) {
/// **** send_IF4 of rxsigF to RAU **** ///
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
if (br_flag == 1) send_IF4p5(ru, ru->proc.frame_prach, ru->proc.subframe_prach, IF4p5_PRACH+1+ce_level);
else
#endif
send_IF4p5(ru, ru->proc.frame_prach, ru->proc.subframe_prach, IF4p5_PRACH);
return;
} else if (eNB!=NULL) {
if ( LOG_DEBUGFLAG(PRACH)) {
int en = dB_fixed(signal_energy((int32_t*)&rxsigF[0][0],840));
if ((en > 60)&&(br_flag==1)) LOG_I(PHY,"PRACH (br_flag %d,ce_level %d, n_ra_prb %d, k %d): Frame %d, Subframe %d => %d dB\n",br_flag,ce_level,n_ra_prb,k,eNB->proc.frame_rx,eNB->proc.subframe_rx,en);
}
}
// in case of RAU and prach received rx_thread wakes up prach
// here onwards is for eNodeB_3GPP or NGFI_RAU_IF4p5
preamble_offset_old = 99;
uint8_t update_TA = 4;
uint8_t update_TA2 = 1;
switch (eNB->frame_parms.N_RB_DL) {
case 6:
update_TA = 16;
break;
case 25:
update_TA = 4;
break;
case 50:
update_TA = 2;
break;
case 75:
update_TA = 3;
update_TA2 = 2;
case 100:
update_TA = 1;
break;
}
*max_preamble_energy=0;
for (preamble_index=0 ; preamble_index<64 ; preamble_index++) {
if (LOG_DEBUGFLAG(PRACH)){
int en = dB_fixed(signal_energy((int32_t*)&rxsigF[0][0],840));
if (en>60) LOG_I(PHY,"frame %d, subframe %d : Trying preamble %d (br_flag %d)\n",ru->proc.frame_prach,subframe,preamble_index,br_flag);
}
if (restricted_set == 0) {
// This is the relative offset in the root sequence table (5.7.2-4 from 36.211) for the given preamble index
preamble_offset = ((NCS==0)? preamble_index : (preamble_index/(N_ZC/NCS)));
if (preamble_offset != preamble_offset_old) {
preamble_offset_old = preamble_offset;
new_dft = 1;
// This is the \nu corresponding to the preamble index
preamble_shift = 0;
}
else {
preamble_shift -= NCS;
if (preamble_shift < 0)
preamble_shift+=N_ZC;
}
} else { // This is the high-speed case
new_dft = 0;
// set preamble_offset to initial rootSequenceIndex and look if we need more root sequences for this
// preamble index and find the corresponding cyclic shift
// Check if all shifts for that root have been processed
if (preamble_index0 == numshift) {
not_found = 1;
new_dft = 1;
preamble_index0 -= numshift;
(preamble_offset==0 && numshift==0) ? (preamble_offset) : (preamble_offset++);
while (not_found == 1) {
// current root depending on rootSequenceIndex
int index = (rootSequenceIndex + preamble_offset) % N_ZC;
if (prach_fmt<4) {
// prach_root_sequence_map points to prach_root_sequence_map0_3
DevAssert( index < sizeof(prach_root_sequence_map0_3) / sizeof(prach_root_sequence_map0_3[0]) );
} else {
// prach_root_sequence_map points to prach_root_sequence_map4
DevAssert( index < sizeof(prach_root_sequence_map4) / sizeof(prach_root_sequence_map4[0]) );
}
u = prach_root_sequence_map[index];
uint16_t n_group_ra = 0;
if ( (du[u]<(N_ZC/3)) && (du[u]>=NCS) ) {
n_shift_ra = du[u]/NCS;
d_start = (du[u]<<1) + (n_shift_ra * NCS);
n_group_ra = N_ZC/d_start;
n_shift_ra_bar = max(0,(N_ZC-(du[u]<<1)-(n_group_ra*d_start))/N_ZC);
} else if ( (du[u]>=(N_ZC/3)) && (du[u]<=((N_ZC - NCS)>>1)) ) {
n_shift_ra = (N_ZC - (du[u]<<1))/NCS;
d_start = N_ZC - (du[u]<<1) + (n_shift_ra * NCS);
n_group_ra = du[u]/d_start;
n_shift_ra_bar = min(n_shift_ra,max(0,(du[u]- (n_group_ra*d_start))/NCS));
} else {
n_shift_ra = 0;
n_shift_ra_bar = 0;
}
// This is the number of cyclic shifts for the current root u
numshift = (n_shift_ra*n_group_ra) + n_shift_ra_bar;
// skip to next root and recompute parameters if numshift==0
(numshift>0) ? (not_found = 0) : (preamble_offset++);
}
}
if (n_shift_ra>0)
preamble_shift = -((d_start * (preamble_index0/n_shift_ra)) + ((preamble_index0%n_shift_ra)*NCS)); // minus because the channel is h(t -\tau + Cv)
else
preamble_shift = 0;
if (preamble_shift < 0)
preamble_shift+=N_ZC;
preamble_index0++;
if (preamble_index == 0)
first_nonzero_root_idx = preamble_offset;
}
// Compute DFT of RX signal (conjugate input, results in conjugate output) for each new rootSequenceIndex
if (LOG_DEBUGFLAG(PRACH)) {
int en = dB_fixed(signal_energy((int32_t*)&rxsigF[0][0],840));
if (en>60) LOG_I(PHY,"frame %d, subframe %d : preamble index %d: offset %d, preamble shift %d (br_flag %d, en %d)\n",
ru->proc.frame_prach,subframe,preamble_index,preamble_offset,preamble_shift,br_flag,en);
}
log2_ifft_size = 10;
fft_size = 6144;
if (new_dft == 1) {
new_dft = 0;
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
if (br_flag == 1) {
Xu=(int16_t*)eNB->X_u_br[ce_level][preamble_offset-first_nonzero_root_idx];
prach_ifft = prach_ifftp[prach_ifft_cnt++];
if (eNB->prach_vars_br.repetition_number[ce_level]==1) memset(prach_ifft,0,((N_ZC==839)?2048:256)*sizeof(int32_t));
}
else
#endif
{
Xu=(int16_t*)eNB->X_u[preamble_offset-first_nonzero_root_idx];
prach_ifft = prach_ifftp[0];
memset(prach_ifft,0,((N_ZC==839) ? 2048 : 256)*sizeof(int32_t));
}
memset(prachF, 0, sizeof(int16_t)*2*1024 );
if (LOG_DUMPFLAG(PRACH)) {
if (prach[0]!= NULL) LOG_M("prach_rx0.m","prach_rx0",prach[0],6144+792,1,1);
LOG_M("prach_rx1.m","prach_rx1",prach[1],6144+792,1,1);
LOG_M("prach_rxF0.m","prach_rxF0",rxsigF[0],24576,1,1);
LOG_M("prach_rxF1.m","prach_rxF1",rxsigF[1],6144,1,1);
}
for (aa=0;aa<nb_rx; aa++) {
// Do componentwise product with Xu* on each antenna
k=0;
for (offset=0; offset<(N_ZC<<1); offset+=2) {
prachF[offset] = (int16_t)(((int32_t)Xu[offset]*rxsigF[aa][k] + (int32_t)Xu[offset+1]*rxsigF[aa][k+1])>>15);
prachF[offset+1] = (int16_t)(((int32_t)Xu[offset]*rxsigF[aa][k+1] - (int32_t)Xu[offset+1]*rxsigF[aa][k])>>15);
k+=2;
if (k==(12*2*fp->ofdm_symbol_size))
k=0;
}
// Now do IFFT of size 1024 (N_ZC=839) or 256 (N_ZC=139)
if (N_ZC == 839) {
log2_ifft_size = 10;
idft1024(prachF,prach_ifft_tmp,1);
// compute energy and accumulate over receive antennas and repetitions for BR
for (i=0;i<2048;i++)
prach_ifft[i] += (prach_ifft_tmp[i<<1]*prach_ifft_tmp[i<<1] + prach_ifft_tmp[1+(i<<1)]*prach_ifft_tmp[1+(i<<1)])>>10;
} else {
idft256(prachF,prach_ifft_tmp,1);
log2_ifft_size = 8;
// compute energy and accumulate over receive antennas and repetitions for BR
for (i=0;i<256;i++)
prach_ifft[i] += (prach_ifft_tmp[i<<1]*prach_ifft_tmp[(i<<1)] + prach_ifft_tmp[1+(i<<1)]*prach_ifft_tmp[1+(i<<1)])>>10;
}
if (LOG_DUMPFLAG(PRACH)) {
if (aa==0) LOG_M("prach_rxF_comp0.m","prach_rxF_comp0",prachF,1024,1,1);
if (aa==1) LOG_M("prach_rxF_comp1.m","prach_rxF_comp1",prachF,1024,1,1);
}
}// antennas_rx
} // new dft
// check energy in nth time shift, for
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
if ((br_flag==0) ||
(eNB->prach_vars_br.repetition_number[ce_level]==
eNB->frame_parms.prach_emtc_config_common.prach_ConfigInfo.prach_numRepetitionPerPreambleAttempt[ce_level]))
#endif
{
if (LOG_DEBUGFLAG(PRACH)){
int en = dB_fixed(signal_energy((int32_t*)&rxsigF[0][0],840));
if (en>60) LOG_I(PHY,"frame %d, subframe %d: Checking for peak in time-domain (br_flag %d, en %d)\n",ru->proc.frame_prach,subframe,br_flag,en);
}
preamble_shift2 = ((preamble_shift==0) ? 0 : ((preamble_shift<<log2_ifft_size)/N_ZC));
for (i=0; i<NCS2; i++) {
lev = (int32_t)prach_ifft[(preamble_shift2+i)];
levdB = dB_fixed_times10(lev);
if (levdB>*max_preamble_energy) {
*max_preamble_energy = levdB;
*max_preamble_delay = ((i*fft_size)>>log2_ifft_size)*update_TA/update_TA2;
*max_preamble = preamble_index;
if (LOG_DEBUGFLAG(PRACH)){
int en = dB_fixed(signal_energy((int32_t*)&rxsigF[0][0],840));
if ((en>60) && (br_flag==1))
LOG_D(PHY,"frame %d, subframe %d : max_preamble_energy %d, max_preamble_delay %d, max_preamble %d (br_flag %d,ce_level %d, levdB %d, lev %d)\n",
ru->proc.frame_prach,subframe,
*max_preamble_energy,*max_preamble_delay,
*max_preamble,br_flag,ce_level,levdB,lev);
}
}
}
}
}// preamble_index
if (LOG_DUMPFLAG(PRACH)) {
int en = dB_fixed(signal_energy((int32_t*)&rxsigF[0][0],840));
if (en>60) {
k = (12*n_ra_prb) - 6*fp->N_RB_UL;
if (k<0) k+=fp->ofdm_symbol_size;
k*=12;
k+=13;
k*=2;
if (br_flag == 0) {
LOG_M("rxsigF.m","prach_rxF",&rxsigF[0][0],12288,1,1);
LOG_M("prach_rxF_comp0.m","prach_rxF_comp0",prachF,1024,1,1);
LOG_M("Xu.m","xu",Xu,N_ZC,1,1);
LOG_M("prach_ifft0.m","prach_t0",prach_ifft,1024,1,1);
}
else {
LOG_E(PHY,"Dumping prach (br_flag %d), k = %d (n_ra_prb %d)\n",br_flag,k,n_ra_prb);
LOG_M("rxsigF_br.m","prach_rxF_br",&rxsigF[0][0],12288,1,1);
LOG_M("prach_rxF_comp0_br.m","prach_rxF_comp0_br",prachF,1024,1,1);
LOG_M("Xu_br.m","xu_br",Xu,N_ZC,1,1);
LOG_M("prach_ifft0_br.m","prach_t0_br",prach_ifft,1024,1,1);
exit(-1);
}
}
} /* LOG_DUMPFLAG(PRACH) */
if (eNB) stop_meas(&eNB->rx_prach);
}