int main(int argc, char **argv) {
cf_t *input_buffer, *sf_symbols = NULL;
int frame_cnt;
ue_sync_t s;
int pos;
pss_synch_t pss;
float peak;
struct timeval t[3];
float mean_ce_time=0;
bool signal_detected;
lte_fft_t fft;
lte_cell_t cell;
bzero(&cell, sizeof(lte_cell_t));
parse_args(argc, argv);
#ifndef DISABLE_GRAPHICS
if (!disable_plots) {
init_plots();
}
#endif
input_init();
if (ue_sync_init(&s, cuhd_set_rx_srate, cuhd_recv_wrapper, uhd)) {
fprintf(stderr, "Error initiating UE sync module\n");
exit(-1);
}
ue_sync_pbch_enable(&s, true);
signal_detected = true;
frame_cnt = 0;
mean_ce_time=0;
uint32_t valid_frames=0;
//uint32_t unaligned = 0;
while (frame_cnt < nof_frames || nof_frames == -1) {
int n = ue_sync_get_buffer(&s, &input_buffer);
if (n < 0) {
fprintf(stderr, "Error calling sync work()\n");
exit(-1);
}
if (n == 1 && ue_sync_get_sfidx(&s) == 0) {
if (signal_detected) {
cell = ue_sync_get_cell(&s);
pss_synch_init_fft(&pss,
SF_LEN(lte_symbol_sz(cell.nof_prb), cell.cp),
lte_symbol_sz(cell.nof_prb));
pss_synch_set_N_id_2(&pss, cell.id%3);
sf_symbols = vec_malloc(SLOT_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
if (!sf_symbols) {
perror("malloc");
exit(-1);
}
lte_fft_init(&fft, cell.cp, cell.nof_prb);
signal_detected = false;
}
mean_ce_time = (float) (mean_ce_time + (float) t[0].tv_usec * valid_frames) / (valid_frames+1);
valid_frames++;
#ifndef DISABLE_GRAPHICS
if (!disable_plots && !(valid_frames % 5) && sf_symbols) {
/* Run FFT for the second slot */
lte_fft_run_slot(&fft, input_buffer, sf_symbols);
int i;
int nof_re = SLOT_LEN_RE(cell.nof_prb, cell.cp);
for (i = 0; i < nof_re; i++) {
tmp_plot[i] = 10 * log10f(cabsf(sf_symbols[i]));
if (isinf(tmp_plot[i])) {
tmp_plot[i] = -80;
}
}
plot_real_setNewData(&poutfft, tmp_plot, nof_re);
}
#endif
pos = pss_synch_find_pss(&pss, input_buffer, &peak, NULL);
/*if (pos > 962 || pos < 958) {
unaligned++;
}
*/
printf("CELL_ID: %3d CFO: %+.4f KHz, SFO: %+.4f Khz, TimeOffset: %4d, Exec: %3.2f\r",
cell.id, ue_sync_get_cfo(&s)/1000, ue_sync_get_sfo(&s)/1000, pos,
s.mean_exec_time);
fflush(stdout);
if (VERBOSE_ISINFO()) {
printf("\n");
}
}
frame_cnt++;
}
printf("\nBye\n");
exit(0);
}
/* Setup USRP or input file */
int iodev_init(iodev_t *q, iodev_cfg_t *config, lte_cell_t *cell, pbch_mib_t *mib) {
if (config->input_file_name) {
mib->phich_resources = R_1;
mib->phich_length = PHICH_NORM;
cell->id = config->cell_id_file;
cell->cp = CPNORM;
cell->nof_ports = config->nof_ports_file;
cell->nof_prb = config->nof_prb_file;
if (filesource_init(&q->fsrc, config->input_file_name, COMPLEX_FLOAT_BIN)) {
return LIBLTE_ERROR;
}
q->mode = FILESOURCE;
int symbol_sz = lte_symbol_sz(cell->nof_prb);
if (symbol_sz > 0) {
q->sf_len = SF_LEN(symbol_sz);
} else {
fprintf(stderr, "Invalid number of PRB %d\n", cell->nof_prb);
return LIBLTE_ERROR;
}
q->input_buffer_file = vec_malloc(q->sf_len * sizeof(cf_t));
if (!q->input_buffer_file) {
perror("malloc");
return LIBLTE_ERROR;
}
q->sf_idx = 9;
} else {
#ifndef DISABLE_UHD
printf("Opening UHD device...\n");
if (cuhd_open(config->uhd_args, &q->uhd)) {
fprintf(stderr, "Error opening uhd\n");
return LIBLTE_ERROR;
}
cuhd_set_rx_gain(q->uhd, config->uhd_gain);
/* set receiver frequency */
cuhd_set_rx_freq(q->uhd, (double) config->uhd_freq);
cuhd_rx_wait_lo_locked(q->uhd);
DEBUG("Set uhd_freq to %.3f MHz\n", (double ) config->uhd_freq);
int n;
ue_celldetect_t cd;
ue_celldetect_result_t found_cells[3];
cf_t *buffer = vec_malloc(sizeof(cf_t) * 96000);
if (!buffer) {
perror("malloc");
return LIBLTE_ERROR;
}
if (ue_celldetect_init(&cd)) {
fprintf(stderr, "Error initiating UE cell detect\n");
exit(-1);
}
n = find_cell(q->uhd, &cd, buffer, found_cells);
if (n < 0) {
fprintf(stderr, "Error searching cell\n");
exit(-1);
}
int max_peak_cell = 0;
float max_peak_value = -1.0;
if (n > 0) {
for (int i=0;i<3;i++) {
if (found_cells[i].peak > max_peak_value) {
max_peak_value = found_cells[i].peak;
max_peak_cell = i;
}
}
if (decode_pbch(q->uhd, buffer, &found_cells[max_peak_cell], 400, mib)) {
fprintf(stderr, "Could not decode PBCH from CELL ID %d\n", found_cells[max_peak_cell].cell_id);
return LIBLTE_ERROR;
}
} else {
fprintf(stderr, "Could not find any cell in this frequency\n");
return LIBLTE_ERROR;
}
free(buffer);
cell->cp = found_cells[max_peak_cell].cp;
cell->id = found_cells[max_peak_cell].cell_id;
cell->nof_prb = mib->nof_prb;
cell->nof_ports = mib->nof_ports;
/* set sampling frequency */
int srate = lte_sampling_freq_hz(cell->nof_prb);
if (srate != -1) {
cuhd_set_rx_srate(q->uhd, (double) srate);
} else {
fprintf(stderr, "Invalid number of PRB %d\n", cell->nof_prb);
return LIBLTE_ERROR;
}
DEBUG("Starting receiver...\n", 0);
cuhd_start_rx_stream(q->uhd);
if (ue_sync_init(&q->sframe, *cell, cuhd_recv_wrapper, q->uhd)) {
fprintf(stderr, "Error initiating ue_sync\n");
return LIBLTE_ERROR;
}
/* Decodes the SSS signal during the tracking phase. Extra overhead, but makes sure we are in the correct subframe */
ue_sync_decode_sss_on_track(&q->sframe, true);
// Here, the subframe length and input buffer is managed by ue_sync
q->mode = UHD;
#else
printf("Error UHD not available. Select an input file\n");
return LIBLTE_ERROR;
#endif
}
memcpy(&q->config, config, sizeof(iodev_cfg_t));
return LIBLTE_SUCCESS;
}
