/*
* 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 1.0 (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/LTE_TRANSPORT/initial_sync.c
* \brief Routines for initial UE synchronization procedure (PSS,SSS,PBCH and frame format detection)
* \author R. Knopp, F. Kaltenberger
* \date 2011
* \version 0.1
* \company Eurecom
* \email: knopp@eurecom.fr,kaltenberger@eurecom.fr
* \note
* \warning
*/
#include "PHY/types.h"
#include "PHY/defs_nr_UE.h"
#include "PHY/phy_extern_nr_ue.h"
#include "PHY/INIT/phy_init.h"
#include "PHY/MODULATION/modulation_UE.h"
#include "nr_transport_proto_ue.h"
#include "PHY/NR_UE_ESTIMATION/nr_estimation.h"
//#include "SCHED/defs.h"
//#include "SCHED/extern.h"
#include "common/utils/LOG/vcd_signal_dumper.h"
#include "common_lib.h"
#include <math.h>
#include "PHY/NR_REFSIG/pss_nr.h"
#include "PHY/NR_REFSIG/sss_nr.h"
#include "PHY/NR_REFSIG/refsig_defs_ue.h"
extern openair0_config_t openair0_cfg[];
//static nfapi_nr_config_request_t config_t;
//static nfapi_nr_config_request_t* config =&config_t;
int cnt=0;
#define DEBUG_INITIAL_SYNCH
// create a new node of SSB structure
NR_UE_SSB* create_ssb_node(uint8_t i, uint8_t h) {
NR_UE_SSB *new_node = (NR_UE_SSB*)malloc(sizeof(NR_UE_SSB));
new_node->i_ssb = i;
new_node->n_hf = h;
new_node->c_re = 0;
new_node->c_im = 0;
new_node->metric = 0;
new_node->next_ssb = NULL;
return new_node;
}
// insertion of the structure in the ordered list (highest metric first)
NR_UE_SSB* insert_into_list(NR_UE_SSB *head, NR_UE_SSB *node) {
if (node->metric > head->metric) {
node->next_ssb = head;
head = node;
return head;
}
NR_UE_SSB *current = head;
while (current->next_ssb !=NULL) {
NR_UE_SSB *temp=current->next_ssb;
if(node->metric > temp->metric) {
node->next_ssb = temp;
current->next_ssb = node;
return head;
}
else
current = temp;
}
current->next_ssb = node;
return head;
}
void free_list(NR_UE_SSB *node) {
if (node->next_ssb != NULL)
free_list(node->next_ssb);
free(node);
}
int nr_pbch_detection(UE_nr_rxtx_proc_t * proc, PHY_VARS_NR_UE *ue, int pbch_initial_symbol, runmode_t mode)
{
NR_DL_FRAME_PARMS *frame_parms=&ue->frame_parms;
int ret =-1;
NR_UE_SSB *best_ssb = NULL;
NR_UE_SSB *current_ssb;
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"[UE%d] Initial sync: starting PBCH detection (rx_offset %d)\n",ue->Mod_id,
ue->rx_offset);
#endif
uint8_t N_L = (frame_parms->Lmax == 4)? 4:8;
uint8_t N_hf = (frame_parms->Lmax == 4)? 2:1;
// loops over possible pbch dmrs cases to retrive best estimated i_ssb (and n_hf for Lmax=4) for multiple ssb detection
for (int hf = 0; hf < N_hf; hf++) {
for (int l = 0; l < N_L ; l++) {
// initialization of structure
current_ssb = create_ssb_node(l,hf);
#if UE_TIMING_TRACE
start_meas(&ue->dlsch_channel_estimation_stats);
#endif
// computing correlation between received DMRS symbols and transmitted sequence for current i_ssb and n_hf
for(int i=pbch_initial_symbol; i<pbch_initial_symbol+3;i++)
nr_pbch_dmrs_correlation(ue,0,0,i,i-pbch_initial_symbol,current_ssb);
#if UE_TIMING_TRACE
stop_meas(&ue->dlsch_channel_estimation_stats);
#endif
current_ssb->metric = current_ssb->c_re*current_ssb->c_re + current_ssb->c_im*current_ssb->c_im;
// generate a list of SSB structures
if (best_ssb == NULL)
best_ssb = current_ssb;
else
best_ssb = insert_into_list(best_ssb,current_ssb);
}
}
NR_UE_SSB *temp_ptr=best_ssb;
while (ret!=0 && temp_ptr != NULL) {
#if UE_TIMING_TRACE
start_meas(&ue->dlsch_channel_estimation_stats);
#endif
// computing channel estimation for selected best ssb
for(int i=pbch_initial_symbol; i<pbch_initial_symbol+3;i++)
nr_pbch_channel_estimation(ue,0,0,i,i-pbch_initial_symbol,temp_ptr->i_ssb,temp_ptr->n_hf);
#if UE_TIMING_TRACE
stop_meas(&ue->dlsch_channel_estimation_stats);
#endif
ret = nr_rx_pbch(ue,
proc,
ue->pbch_vars[0],
frame_parms,
0,
temp_ptr->i_ssb,
SISO,
ue->high_speed_flag);
temp_ptr=temp_ptr->next_ssb;
}
free_list(best_ssb);
if (ret==0) {
frame_parms->nb_antenna_ports_gNB = 1; //pbch_tx_ant;
// set initial transmission mode to 1 or 2 depending on number of detected TX antennas
//frame_parms->mode1_flag = (pbch_tx_ant==1);
// openair_daq_vars.dlsch_transmission_mode = (pbch_tx_ant>1) ? 2 : 1;
// flip byte endian on 24-bits for MIB
// dummy = ue->pbch_vars[0]->decoded_output[0];
// ue->pbch_vars[0]->decoded_output[0] = ue->pbch_vars[0]->decoded_output[2];
// ue->pbch_vars[0]->decoded_output[2] = dummy;
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"[UE%d] Initial sync: pbch decoded sucessfully\n",ue->Mod_id);
#endif
return(0);
} else {
return(-1);
}
}
char duplex_string[2][4] = {"FDD","TDD"};
char prefix_string[2][9] = {"NORMAL","EXTENDED"};
int nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, runmode_t mode, int n_frames)
{
int32_t sync_pos, sync_pos_frame; // k_ssb, N_ssb_crb, sync_pos2,
int32_t metric_tdd_ncp=0;
uint8_t phase_tdd_ncp;
double im, re;
int is;
NR_DL_FRAME_PARMS *fp = &ue->frame_parms;
int ret=-1;
int rx_power=0; //aarx,
VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_NR_INITIAL_UE_SYNC, VCD_FUNCTION_IN);
LOG_D(PHY,"nr_initial sync ue RB_DL %d\n", fp->N_RB_DL);
/* Initial synchronisation
*
* 1 radio frame = 10 ms
* <--------------------------------------------------------------------------->
* -----------------------------------------------------------------------------
* | Received UE data buffer |
* ----------------------------------------------------------------------------
* --------------------------
* <-------------->| pss | pbch | sss | pbch |
* --------------------------
* sync_pos SS/PBCH block
*/
cnt++;
if (1){ // (cnt>100)
cnt =0;
// initial sync performed on two successive frames, if pbch passes on first frame, no need to process second frame
// only one frame is used for symulation tools
for(is=0; is<n_frames;is++) {
/* process pss search on received buffer */
sync_pos = pss_synchro_nr(ue, is, NO_RATE_CHANGE);
if (sync_pos >= fp->nb_prefix_samples)
ue->ssb_offset = sync_pos - fp->nb_prefix_samples;
else
ue->ssb_offset = sync_pos + (fp->samples_per_subframe * 10) - fp->nb_prefix_samples;
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"[UE%d] Initial sync : Estimated PSS position %d, Nid2 %d\n", ue->Mod_id, sync_pos,ue->common_vars.eNb_id);
LOG_I(PHY,"sync_pos %d ssb_offset %d \n",sync_pos,ue->ssb_offset);
#endif
// digital compensation of FFO for SSB symbols
if (ue->UE_fo_compensation){
double s_time = 1/(1.0e3*fp->samples_per_subframe); // sampling time
double off_angle = -2*M_PI*s_time*(ue->common_vars.freq_offset); // offset rotation angle compensation per sample
int start = is*fp->samples_per_frame+ue->ssb_offset; // start for offset correction is at ssb_offset (pss time position)
int end = start + 4*(fp->ofdm_symbol_size + fp->nb_prefix_samples); // loop over samples in 4 symbols (ssb size), including prefix
for(int n=start; n<end; n++){
for (int ar=0; ar<fp->nb_antennas_rx; ar++) {
re = ((double)(((short *)ue->common_vars.rxdata[ar]))[2*n]);
im = ((double)(((short *)ue->common_vars.rxdata[ar]))[2*n+1]);
((short *)ue->common_vars.rxdata[ar])[2*n] = (short)(round(re*cos(n*off_angle) - im*sin(n*off_angle)));
((short *)ue->common_vars.rxdata[ar])[2*n+1] = (short)(round(re*sin(n*off_angle) + im*cos(n*off_angle)));
}
}
}
/* check that SSS/PBCH block is continuous inside the received buffer */
if (sync_pos < (NR_NUMBER_OF_SUBFRAMES_PER_FRAME*fp->samples_per_subframe - (NB_SYMBOLS_PBCH * fp->ofdm_symbol_size))) {
/* slop_fep function works for lte and takes into account begining of frame with prefix for subframe 0 */
/* for NR this is not the case but slot_fep is still used for computing FFT of samples */
/* in order to achieve correct processing for NR prefix samples is forced to 0 and then restored after function call */
/* symbol number are from beginning of SS/PBCH blocks as below: */
/* Signal PSS PBCH SSS PBCH */
/* symbol number 0 1 2 3 */
/* time samples in buffer rxdata are used as input of FFT -> FFT results are stored in the frequency buffer rxdataF */
/* rxdataF stores SS/PBCH from beginning of buffers in the same symbol order as in time domain */
for(int i=0; i<4;i++)
nr_slot_fep_init_sync(ue,
i,
0,
is*fp->samples_per_frame+ue->ssb_offset,
0);
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"Calling sss detection (normal CP)\n");
#endif
rx_sss_nr(ue,&metric_tdd_ncp,&phase_tdd_ncp);
nr_gold_pbch(ue);
ret = nr_pbch_detection(proc, ue,1,mode); // start pbch detection at first symbol after pss
if (ret == 0) {
// sync at symbol ue->symbol_offset
// computing the offset wrt the beginning of the frame
sync_pos_frame = (fp->ofdm_symbol_size + fp->nb_prefix_samples0)+((ue->symbol_offset)-1)*(fp->ofdm_symbol_size + fp->nb_prefix_samples);
if (ue->ssb_offset < sync_pos_frame)
ue->rx_offset = fp->samples_per_frame - sync_pos_frame + ue->ssb_offset;
else
ue->rx_offset = ue->ssb_offset - sync_pos_frame;
ue->init_sync_frame = is;
}
nr_gold_pdcch(ue,0, 2);
/*
int nb_prefix_samples0 = fp->nb_prefix_samples0;
fp->nb_prefix_samples0 = fp->nb_prefix_samples;
nr_slot_fep(ue,0, 0, ue->ssb_offset, 0, NR_PDCCH_EST);
nr_slot_fep(ue,1, 0, ue->ssb_offset, 0, NR_PDCCH_EST);
fp->nb_prefix_samples0 = nb_prefix_samples0;
LOG_I(PHY,"[UE %d] AUTOTEST Cell Sync : frame = %d, rx_offset %d, freq_offset %d \n",
ue->Mod_id,
ue->proc.proc_rxtx[0].frame_rx,
ue->rx_offset,
ue->common_vars.freq_offset );
*/
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"TDD Normal prefix: CellId %d metric %d, phase %d, pbch %d\n",
fp->Nid_cell,metric_tdd_ncp,phase_tdd_ncp,ret);
#endif
}
else {
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"TDD Normal prefix: SSS error condition: sync_pos %d\n", sync_pos);
#endif
}
if (ret == 0) break;
}
}
else {
ret = -1;
}
/* Consider this is a false detection if the offset is > 1000 Hz
Not to be used now that offest estimation is in place
if( (abs(ue->common_vars.freq_offset) > 150) && (ret == 0) )
{
ret=-1;
#if DISABLE_LOG_X
printf("Ignore MIB with high freq offset [%d Hz] estimation \n",ue->common_vars.freq_offset);
#else
LOG_E(HW, "Ignore MIB with high freq offset [%d Hz] estimation \n",ue->common_vars.freq_offset);
#endif
}*/
if (ret==0) { // PBCH found so indicate sync to higher layers and configure frame parameters
//#ifdef DEBUG_INITIAL_SYNCH
#if DISABLE_LOG_X
printf("[UE%d] In synch, rx_offset %d samples\n",ue->Mod_id, ue->rx_offset);
#else
LOG_I(PHY, "[UE%d] In synch, rx_offset %d samples\n",ue->Mod_id, ue->rx_offset);
#endif
//#endif
ue->is_synchronized_on_frame = is; // to notify on which of the two frames sync was successful
if (ue->UE_scan_carrier == 0) {
#if UE_AUTOTEST_TRACE
LOG_I(PHY,"[UE %d] AUTOTEST Cell Sync : rx_offset %d, freq_offset %d \n",
ue->Mod_id,
ue->rx_offset,
ue->common_vars.freq_offset );
#endif
// send sync status to higher layers later when timing offset converge to target timing
ue->pbch_vars[0]->pdu_errors_conseq=0;
}
LOG_I(PHY, "[UE %d] RRC Measurements => rssi %3.1f dBm (dig %3.1f dB, gain %d), N0 %d dBm, rsrp %3.1f dBm/RE, rsrq %3.1f dB\n",ue->Mod_id,
10*log10(ue->measurements.rssi)-ue->rx_total_gain_dB,
10*log10(ue->measurements.rssi),
ue->rx_total_gain_dB,
ue->measurements.n0_power_tot_dBm,
10*log10(ue->measurements.rsrp[0])-ue->rx_total_gain_dB,
(10*log10(ue->measurements.rsrq[0])));
/* LOG_I(PHY, "[UE %d] Frame %d MIB Information => %s, %s, NidCell %d, N_RB_DL %d, PHICH DURATION %d, PHICH RESOURCE %s, TX_ANT %d\n",
ue->Mod_id,
ue->proc.proc_rxtx[0].frame_rx,
duplex_string[fp->frame_type],
prefix_string[fp->Ncp],
fp->Nid_cell,
fp->N_RB_DL,
fp->phich_config_common.phich_duration,
phich_string[fp->phich_config_common.phich_resource],
fp->nb_antenna_ports_gNB);*/
#if defined(OAI_USRP) || defined(EXMIMO) || defined(OAI_BLADERF) || defined(OAI_LMSSDR) || defined(OAI_ADRV9371_ZC706)
LOG_I(PHY, "[UE %d] Measured Carrier Frequency %.0f Hz (offset %d Hz)\n",
ue->Mod_id,
openair0_cfg[0].rx_freq[0]+ue->common_vars.freq_offset,
ue->common_vars.freq_offset);
#endif
} else {
#ifdef DEBUG_INITIAL_SYNC
LOG_I(PHY,"[UE%d] Initial sync : PBCH not ok\n",ue->Mod_id);
LOG_I(PHY,"[UE%d] Initial sync : Estimated PSS position %d, Nid2 %d\n",ue->Mod_id,sync_pos,ue->common_vars.eNb_id);
LOG_I(PHY,"[UE%d] Initial sync : Estimated Nid_cell %d, Frame_type %d\n",ue->Mod_id,
frame_parms->Nid_cell,frame_parms->frame_type);
#endif
ue->UE_mode[0] = NOT_SYNCHED;
ue->pbch_vars[0]->pdu_errors_last=ue->pbch_vars[0]->pdu_errors;
ue->pbch_vars[0]->pdu_errors++;
ue->pbch_vars[0]->pdu_errors_conseq++;
}
// gain control
if (ret!=0) { //we are not synched, so we cannot use rssi measurement (which is based on channel estimates)
rx_power = 0;
// do a measurement on the best guess of the PSS
//for (aarx=0; aarx<frame_parms->nb_antennas_rx; aarx++)
// rx_power += signal_energy(&ue->common_vars.rxdata[aarx][sync_pos2],
// frame_parms->ofdm_symbol_size+frame_parms->nb_prefix_samples);
/*
// do a measurement on the full frame
for (aarx=0; aarx<frame_parms->nb_antennas_rx; aarx++)
rx_power += signal_energy(&ue->common_vars.rxdata[aarx][0],
frame_parms->samples_per_subframe*10);
*/
// we might add a low-pass filter here later
ue->measurements.rx_power_avg[0] = rx_power/fp->nb_antennas_rx;
ue->measurements.rx_power_avg_dB[0] = dB_fixed(ue->measurements.rx_power_avg[0]);
#ifdef DEBUG_INITIAL_SYNCH
LOG_I(PHY,"[UE%d] Initial sync : Estimated power: %d dB\n",ue->Mod_id,ue->measurements.rx_power_avg_dB[0] );
#endif
#ifndef OAI_USRP
#ifndef OAI_BLADERF
#ifndef OAI_LMSSDR
#ifndef OAI_ADRV9371_ZC706
//phy_adjust_gain(ue,ue->measurements.rx_power_avg_dB[0],0);
#endif
#endif
#endif
#endif
}
else {
#ifndef OAI_USRP
#ifndef OAI_BLADERF
#ifndef OAI_LMSSDR
#ifndef OAI_ADRV9371_ZC706
//phy_adjust_gain(ue,dB_fixed(ue->measurements.rssi),0);
#endif
#endif
#endif
#endif
}
// exit_fun("debug exit");
VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_NR_INITIAL_UE_SYNC, VCD_FUNCTION_OUT);
return ret;
}