srsLTE/lib/examples/cell_measurement.c

422 lines
13 KiB
C

/**
*
* \section COPYRIGHT
*
* Copyright 2013-2015 Software Radio Systems Limited
*
* \section LICENSE
*
* This file is part of the srsLTE library.
*
* srsLTE is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* srsLTE is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* A copy of the GNU Affero General Public License can be found in
* the LICENSE file in the top-level directory of this distribution
* and at http://www.gnu.org/licenses/.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <math.h>
#include <sys/time.h>
#include <unistd.h>
#include <assert.h>
#include <signal.h>
#define ENABLE_AGC_DEFAULT
#include "srslte/srslte.h"
#include "srslte/phy/rf/rf.h"
#include "srslte/phy/rf/rf_utils.h"
#include "srslte/common/crash_handler.h"
cell_search_cfg_t cell_detect_config = {
SRSLTE_DEFAULT_MAX_FRAMES_PBCH,
SRSLTE_DEFAULT_MAX_FRAMES_PSS,
SRSLTE_DEFAULT_NOF_VALID_PSS_FRAMES,
0
};
/**********************************************************************
* Program arguments processing
***********************************************************************/
typedef struct {
int nof_subframes;
bool disable_plots;
int force_N_id_2;
char *rf_args;
float rf_freq;
float rf_gain;
}prog_args_t;
void args_default(prog_args_t *args) {
args->nof_subframes = -1;
args->force_N_id_2 = -1; // Pick the best
args->rf_args = "";
args->rf_freq = -1.0;
#ifdef ENABLE_AGC_DEFAULT
args->rf_gain = -1;
#else
args->rf_gain = 50;
#endif
}
void usage(prog_args_t *args, char *prog) {
printf("Usage: %s [aglnv] -f rx_frequency (in Hz)\n", prog);
printf("\t-a RF args [Default %s]\n", args->rf_args);
printf("\t-g RF RX gain [Default %.2f dB]\n", args->rf_gain);
printf("\t-l Force N_id_2 [Default best]\n");
printf("\t-n nof_subframes [Default %d]\n", args->nof_subframes);
printf("\t-v [set srslte_verbose to debug, default none]\n");
}
int parse_args(prog_args_t *args, int argc, char **argv) {
int opt;
args_default(args);
while ((opt = getopt(argc, argv, "aglnvf")) != -1) {
switch (opt) {
case 'a':
args->rf_args = argv[optind];
break;
case 'g':
args->rf_gain = atof(argv[optind]);
break;
case 'f':
args->rf_freq = atof(argv[optind]);
break;
case 'n':
args->nof_subframes = atoi(argv[optind]);
break;
case 'l':
args->force_N_id_2 = atoi(argv[optind]);
break;
case 'v':
srslte_verbose++;
break;
default:
usage(args, argv[0]);
return -1;
}
}
if (args->rf_freq < 0) {
usage(args, argv[0]);
return -1;
}
return 0;
}
/**********************************************************************/
/* TODO: Do something with the output data */
uint8_t *data[SRSLTE_MAX_CODEWORDS];
bool go_exit = false;
void sig_int_handler(int signo)
{
printf("SIGINT received. Exiting...\n");
if (signo == SIGINT) {
go_exit = true;
}
}
int srslte_rf_recv_wrapper(void *h, cf_t *data[SRSLTE_MAX_PORTS], uint32_t nsamples, srslte_timestamp_t *q) {
DEBUG(" ---- Receive %d samples ---- \n", nsamples);
return srslte_rf_recv(h, data[0], nsamples, 1);
}
enum receiver_state { DECODE_MIB, DECODE_SIB, MEASURE} state;
#define MAX_SINFO 10
#define MAX_NEIGHBOUR_CELLS 128
int main(int argc, char **argv) {
int ret;
cf_t *sf_buffer[SRSLTE_MAX_PORTS] = {NULL, NULL};
prog_args_t prog_args;
srslte_cell_t cell;
int64_t sf_cnt;
srslte_ue_sync_t ue_sync;
srslte_ue_mib_t ue_mib;
srslte_rf_t rf;
srslte_ue_dl_t ue_dl;
srslte_ofdm_t fft;
srslte_chest_dl_t chest;
uint32_t nframes=0;
uint32_t nof_trials = 0;
uint32_t sfn = 0; // system frame number
int n;
uint8_t bch_payload[SRSLTE_BCH_PAYLOAD_LEN];
int sfn_offset;
float rssi_utra=0,rssi=0, rsrp=0, rsrq=0, snr=0;
cf_t *ce[SRSLTE_MAX_PORTS];
float cfo = 0;
bool acks[SRSLTE_MAX_CODEWORDS] = {false};
srslte_debug_handle_crash(argc, argv);
if (parse_args(&prog_args, argc, argv)) {
exit(-1);
}
printf("Opening RF device...\n");
if (srslte_rf_open(&rf, prog_args.rf_args)) {
fprintf(stderr, "Error opening rf\n");
exit(-1);
}
if (prog_args.rf_gain > 0) {
srslte_rf_set_rx_gain(&rf, prog_args.rf_gain);
} else {
printf("Starting AGC thread...\n");
if (srslte_rf_start_gain_thread(&rf, false)) {
fprintf(stderr, "Error opening rf\n");
exit(-1);
}
srslte_rf_set_rx_gain(&rf, 50);
}
sf_buffer[0] = srslte_vec_malloc(3*sizeof(cf_t)*SRSLTE_SF_LEN_PRB(100));
for (int i = 0; i < SRSLTE_MAX_CODEWORDS; i++) {
data[i] = srslte_vec_malloc(sizeof(uint8_t) * 1500*8);
}
sigset_t sigset;
sigemptyset(&sigset);
sigaddset(&sigset, SIGINT);
sigprocmask(SIG_UNBLOCK, &sigset, NULL);
signal(SIGINT, sig_int_handler);
srslte_rf_set_master_clock_rate(&rf, 30.72e6);
/* set receiver frequency */
srslte_rf_set_rx_freq(&rf, (double) prog_args.rf_freq);
srslte_rf_rx_wait_lo_locked(&rf);
printf("Tunning receiver to %.3f MHz\n", (double ) prog_args.rf_freq/1000000);
cell_detect_config.init_agc = (prog_args.rf_gain<0);
uint32_t ntrial=0;
do {
ret = rf_search_and_decode_mib(&rf, 1, &cell_detect_config, prog_args.force_N_id_2, &cell, &cfo);
if (ret < 0) {
fprintf(stderr, "Error searching for cell\n");
exit(-1);
} else if (ret == 0 && !go_exit) {
printf("Cell not found after %d trials. Trying again (Press Ctrl+C to exit)\n", ntrial++);
}
} while (ret == 0 && !go_exit);
if (go_exit) {
exit(0);
}
/* set sampling frequency */
int srate = srslte_sampling_freq_hz(cell.nof_prb);
if (srate != -1) {
if (srate < 10e6) {
srslte_rf_set_master_clock_rate(&rf, 4*srate);
} else {
srslte_rf_set_master_clock_rate(&rf, srate);
}
printf("Setting sampling rate %.2f MHz\n", (float) srate/1000000);
float srate_rf = srslte_rf_set_rx_srate(&rf, (double) srate);
if (srate_rf != srate) {
fprintf(stderr, "Could not set sampling rate\n");
exit(-1);
}
} else {
fprintf(stderr, "Invalid number of PRB %d\n", cell.nof_prb);
exit(-1);
}
INFO("Stopping RF and flushing buffer...\n");
srslte_rf_stop_rx_stream(&rf);
srslte_rf_flush_buffer(&rf);
if (srslte_ue_sync_init_multi(&ue_sync, cell.nof_prb, cell.id==1000, srslte_rf_recv_wrapper, 1, (void*) &rf)) {
fprintf(stderr, "Error initiating ue_sync\n");
return -1;
}
if (srslte_ue_sync_set_cell(&ue_sync, cell)) {
fprintf(stderr, "Error initiating ue_sync\n");
return -1;
}
if (srslte_ue_dl_init(&ue_dl, sf_buffer, cell.nof_prb, 1)) {
fprintf(stderr, "Error initiating UE downlink processing module\n");
return -1;
}
if (srslte_ue_dl_set_cell(&ue_dl, cell)) {
fprintf(stderr, "Error initiating UE downlink processing module\n");
return -1;
}
if (srslte_ue_mib_init(&ue_mib, sf_buffer, cell.nof_prb)) {
fprintf(stderr, "Error initaiting UE MIB decoder\n");
return -1;
}
if (srslte_ue_mib_set_cell(&ue_mib, cell)) {
fprintf(stderr, "Error initaiting UE MIB decoder\n");
return -1;
}
/* Configure downlink receiver for the SI-RNTI since will be the only one we'll use */
srslte_ue_dl_set_rnti(&ue_dl, SRSLTE_SIRNTI);
/* Initialize subframe counter */
sf_cnt = 0;
int sf_re = SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp);
cf_t *sf_symbols = srslte_vec_malloc(sf_re * sizeof(cf_t));
for (int i=0;i<SRSLTE_MAX_PORTS;i++) {
ce[i] = srslte_vec_malloc(sizeof(cf_t) * sf_re);
}
if (srslte_ofdm_rx_init(&fft, cell.cp, sf_buffer[0], sf_symbols, cell.nof_prb)) {
fprintf(stderr, "Error initiating FFT\n");
return -1;
}
if (srslte_chest_dl_init(&chest, cell.nof_prb)) {
fprintf(stderr, "Error initiating channel estimator\n");
return -1;
}
if (srslte_chest_dl_set_cell(&chest, cell)) {
fprintf(stderr, "Error initiating channel estimator\n");
return -1;
}
srslte_rf_start_rx_stream(&rf, false);
float rx_gain_offset = 0;
/* Main loop */
while ((sf_cnt < prog_args.nof_subframes || prog_args.nof_subframes == -1) && !go_exit) {
ret = srslte_ue_sync_zerocopy_multi(&ue_sync, sf_buffer);
if (ret < 0) {
fprintf(stderr, "Error calling srslte_ue_sync_work()\n");
}
/* srslte_ue_sync_get_buffer returns 1 if successfully read 1 aligned subframe */
if (ret == 1) {
switch (state) {
case DECODE_MIB:
if (srslte_ue_sync_get_sfidx(&ue_sync) == 0) {
srslte_pbch_decode_reset(&ue_mib.pbch);
n = srslte_ue_mib_decode(&ue_mib, bch_payload, NULL, &sfn_offset);
if (n < 0) {
fprintf(stderr, "Error decoding UE MIB\n");
return -1;
} else if (n == SRSLTE_UE_MIB_FOUND) {
srslte_pbch_mib_unpack(bch_payload, &cell, &sfn);
printf("Decoded MIB. SFN: %d, offset: %d\n", sfn, sfn_offset);
sfn = (sfn + sfn_offset)%1024;
state = DECODE_SIB;
}
}
break;
case DECODE_SIB:
/* We are looking for SI Blocks, search only in appropiate places */
if ((srslte_ue_sync_get_sfidx(&ue_sync) == 5 && (sfn%2)==0)) {
n = srslte_ue_dl_decode(&ue_dl, data, 0, sfn*10+srslte_ue_sync_get_sfidx(&ue_sync), acks);
if (n < 0) {
fprintf(stderr, "Error decoding UE DL\n");fflush(stdout);
return -1;
} else if (n == 0) {
printf("CFO: %+6.4f kHz, SFO: %+6.4f kHz, PDCCH-Det: %.3f\r",
srslte_ue_sync_get_cfo(&ue_sync)/1000, srslte_ue_sync_get_sfo(&ue_sync)/1000,
(float) ue_dl.nof_detected/nof_trials);
nof_trials++;
} else {
printf("Decoded SIB1. Payload: ");
srslte_vec_fprint_byte(stdout, data[0], n/8);;
state = MEASURE;
}
}
break;
case MEASURE:
if (srslte_ue_sync_get_sfidx(&ue_sync) == 5) {
/* Run FFT for all subframe data */
srslte_ofdm_rx_sf(&fft);
srslte_chest_dl_estimate(&chest, sf_symbols, ce, srslte_ue_sync_get_sfidx(&ue_sync));
rssi = SRSLTE_VEC_EMA(srslte_vec_avg_power_cf(sf_buffer[0],SRSLTE_SF_LEN(srslte_symbol_sz(cell.nof_prb))),rssi,0.05);
rssi_utra = SRSLTE_VEC_EMA(srslte_chest_dl_get_rssi(&chest),rssi_utra,0.05);
rsrq = SRSLTE_VEC_EMA(srslte_chest_dl_get_rsrq(&chest),rsrq,0.05);
rsrp = SRSLTE_VEC_EMA(srslte_chest_dl_get_rsrp(&chest),rsrp,0.05);
snr = SRSLTE_VEC_EMA(srslte_chest_dl_get_snr(&chest),snr,0.05);
nframes++;
}
if ((nframes%100) == 0 || rx_gain_offset == 0) {
if (srslte_rf_has_rssi(&rf)) {
rx_gain_offset = 30+10*log10(rssi*1000)-srslte_rf_get_rssi(&rf);
} else {
rx_gain_offset = srslte_rf_get_rx_gain(&rf);
}
}
// Plot and Printf
if ((nframes%10) == 0) {
printf("CFO: %+8.4f kHz, SFO: %+8.4f Hz, RSSI: %5.1f dBm, RSSI/ref-symbol: %+5.1f dBm, "
"RSRP: %+5.1f dBm, RSRQ: %5.1f dB, SNR: %5.1f dB\r",
srslte_ue_sync_get_cfo(&ue_sync)/1000, srslte_ue_sync_get_sfo(&ue_sync),
10*log10(rssi*1000) - rx_gain_offset,
10*log10(rssi_utra*1000)- rx_gain_offset,
10*log10(rsrp*1000) - rx_gain_offset,
10*log10(rsrq), 10*log10(snr));
if (srslte_verbose != SRSLTE_VERBOSE_NONE) {
printf("\n");
}
}
break;
}
if (srslte_ue_sync_get_sfidx(&ue_sync) == 9) {
sfn++;
if (sfn == 1024) {
sfn = 0;
}
}
} else if (ret == 0) {
printf("Finding PSS... Peak: %8.1f, FrameCnt: %d, State: %d\r",
srslte_sync_get_peak_value(&ue_sync.sfind),
ue_sync.frame_total_cnt, ue_sync.state);
}
sf_cnt++;
} // Main loop
for (int i = 0; i < SRSLTE_MAX_CODEWORDS; i++) {
if (data[i]) {
free(data[i]);
}
}
srslte_ue_sync_free(&ue_sync);
srslte_rf_close(&rf);
printf("\nBye\n");
exit(0);
}