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548 lines
16 KiB
C
548 lines
16 KiB
C
/**
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*
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* \section COPYRIGHT
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*
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* Copyright 2013-2014 The libLTE Developers. See the
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* COPYRIGHT file at the top-level directory of this distribution.
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*
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* \section LICENSE
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*
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* This file is part of the libLTE library.
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*
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* libLTE is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation, either version 3 of
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* the License, or (at your option) any later version.
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*
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* libLTE is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* A copy of the GNU Lesser General Public License can be found in
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* the LICENSE file in the top-level directory of this distribution
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* and at http://www.gnu.org/licenses/.
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*
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <strings.h>
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#include <unistd.h>
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#include <math.h>
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#include <sys/time.h>
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#include <unistd.h>
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#include <assert.h>
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#include <signal.h>
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#include <pthread.h>
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#include <semaphore.h>
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#include "liblte/rrc/rrc.h"
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#include "liblte/phy/phy.h"
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#include "liblte/cuhd/cuhd.h"
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#include "cuhd_utils.h"
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cell_search_cfg_t cell_detect_config = {
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5000,
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100, // nof_frames_total
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16.0 // threshold
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};
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#define B210_DEFAULT_GAIN 40.0
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#define B210_DEFAULT_GAIN_CORREC 110.0 // Gain of the Rx chain when the gain is set to 40
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float gain_offset = B210_DEFAULT_GAIN_CORREC;
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/**********************************************************************
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* Program arguments processing
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***********************************************************************/
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typedef struct {
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int nof_subframes;
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int force_N_id_2;
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uint16_t rnti;
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uint32_t file_nof_prb;
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char *uhd_args;
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float uhd_rx_freq;
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float uhd_tx_freq;
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float uhd_tx_freq_offset;
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float uhd_gain;
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}prog_args_t;
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void args_default(prog_args_t *args) {
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args->nof_subframes = -1;
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args->rnti = SIRNTI;
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args->force_N_id_2 = -1; // Pick the best
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args->file_nof_prb = 6;
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args->uhd_args = "";
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args->uhd_rx_freq = 2112500000.0;
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args->uhd_tx_freq = 1922500000.0;
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args->uhd_tx_freq_offset = 8000000.0;
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args->uhd_gain = 60.0;
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}
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void usage(prog_args_t *args, char *prog) {
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printf("Usage: %s [agfFrlnv]\n", prog);
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printf("\t-a UHD args [Default %s]\n", args->uhd_args);
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printf("\t-g UHD TX/RX gain [Default %.2f dB]\n", args->uhd_gain);
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printf("\t-f UHD RX freq [Default %.1f MHz]\n", args->uhd_rx_freq/1000000);
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printf("\t-F UHD TX freq [Default %.1f MHz]\n", args->uhd_tx_freq/1000000);
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printf("\t-r RNTI [Default 0x%x]\n",args->rnti);
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printf("\t-l Force N_id_2 [Default best]\n");
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printf("\t-n nof_subframes [Default %d]\n", args->nof_subframes);
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printf("\t-v [set verbose to debug, default none]\n");
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}
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void parse_args(prog_args_t *args, int argc, char **argv) {
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int opt;
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args_default(args);
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while ((opt = getopt(argc, argv, "agfFrlnv")) != -1) {
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switch (opt) {
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case 'a':
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args->uhd_args = argv[optind];
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break;
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case 'g':
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args->uhd_gain = atof(argv[optind]);
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break;
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case 'f':
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args->uhd_rx_freq = atof(argv[optind]);
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break;
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case 'F':
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args->uhd_tx_freq = atof(argv[optind]);
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break;
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case 'n':
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args->nof_subframes = atoi(argv[optind]);
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break;
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case 'r':
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args->rnti = atoi(argv[optind]);
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break;
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case 'l':
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args->force_N_id_2 = atoi(argv[optind]);
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break;
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case 'v':
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verbose++;
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break;
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default:
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usage(args, argv[0]);
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exit(-1);
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}
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}
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if (args->uhd_tx_freq < 0 && args->uhd_rx_freq < 0) {
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usage(args, argv[0]);
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exit(-1);
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}
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}
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/**********************************************************************/
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/* TODO: Do something with the output data */
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uint8_t data_rx[20000];
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bool go_exit = false;
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void sig_int_handler(int signo)
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{
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if (signo == SIGINT) {
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go_exit = true;
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}
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}
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int cuhd_recv_wrapper_timed(void *h, void *data, uint32_t nsamples, timestamp_t *uhd_time) {
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DEBUG(" ---- Receive %d samples ---- \n", nsamples);
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return cuhd_recv_with_time(h, data, nsamples, true, &uhd_time->full_secs, &uhd_time->frac_secs);
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}
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extern float mean_exec_time;
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enum receiver_state { DECODE_MIB, SEND_PRACH, RECV_RAR} state;
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#define NOF_PRACH_SEQUENCES 52
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ue_dl_t ue_dl;
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ue_ul_t ue_ul;
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ue_sync_t ue_sync;
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prach_t prach;
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cf_t *prach_buffers[NOF_PRACH_SEQUENCES];
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int prach_buffer_len;
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prog_args_t prog_args;
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uint32_t sfn = 0; // system frame number
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cf_t *sf_buffer = NULL;
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int generate_prach_sequences(){
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for(int i=0;i<NOF_PRACH_SEQUENCES;i++){
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if(prach_gen(&prach, i, 2, prach_buffers[i])){
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fprintf(stderr, "Error generating prach sequence\n");
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return -1;
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}
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}
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return 0;
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}
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typedef enum{
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rar_tpc_n6dB = 0,
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rar_tpc_n4dB,
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rar_tpc_n2dB,
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rar_tpc_0dB,
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rar_tpc_2dB,
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rar_tpc_4dB,
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rar_tpc_6dB,
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rar_tpc_8dB,
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rar_tpc_n_items,
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}rar_tpc_command_t;
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static const char tpc_command_text[rar_tpc_n_items][8] = {"-6dB", "-4dB", "-2dB", "0dB", "2dB", "4dB", "6dB", "8dB"};
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typedef enum{
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rar_header_type_bi = 0,
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rar_header_type_rapid,
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rar_header_type_n_items,
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}rar_header_t;
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static const char rar_header_text[rar_header_type_n_items][8] = {"BI", "RAPID"};
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typedef struct {
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rar_header_t hdr_type;
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bool hopping_flag;
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rar_tpc_command_t tpc_command;
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bool ul_delay;
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bool csi_req;
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uint16_t rba;
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uint16_t timing_adv_cmd;
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uint16_t temp_c_rnti;
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uint8_t mcs;
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uint8_t RAPID;
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uint8_t BI;
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}rar_msg_t;
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char *bool_to_string(bool x) {
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if (x) {
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return "Enabled";
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} else {
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return "Disabled";
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}
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}
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void rar_msg_fprint(FILE *stream, rar_msg_t *msg)
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{
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fprintf(stream, "Header type: %s\n", rar_header_text[msg->hdr_type]);
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fprintf(stream, "Hopping flag: %s\n", bool_to_string(msg->hopping_flag));
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fprintf(stream, "TPC command: %s\n", tpc_command_text[msg->tpc_command]);
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fprintf(stream, "UL delay: %s\n", bool_to_string(msg->ul_delay));
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fprintf(stream, "CSI required: %s\n", bool_to_string(msg->csi_req));
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fprintf(stream, "RBA: %d\n", msg->rba);
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fprintf(stream, "TA: %d\n", msg->timing_adv_cmd);
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fprintf(stream, "T-CRNTI: %d\n", msg->temp_c_rnti);
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fprintf(stream, "MCS: %d\n", msg->mcs);
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fprintf(stream, "RAPID: %d\n", msg->RAPID);
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fprintf(stream, "BI: %d\n", msg->BI);
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}
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int rar_unpack(uint8_t *buffer, rar_msg_t *msg)
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{
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int ret = LIBLTE_ERROR;
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uint8_t *ptr = buffer;
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if(buffer != NULL &&
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msg != NULL)
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{
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ptr++;
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msg->hdr_type = *ptr++;
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if(msg->hdr_type == rar_header_type_bi) {
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ptr += 2;
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msg->BI = bit_unpack(&ptr, 4);
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ret = LIBLTE_SUCCESS;
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} else if (msg->hdr_type == rar_header_type_rapid) {
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msg->RAPID = bit_unpack(&ptr, 6);
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ptr++;
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msg->timing_adv_cmd = bit_unpack(&ptr, 11);
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msg->hopping_flag = *ptr++;
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msg->rba = bit_unpack(&ptr, 10);
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msg->mcs = bit_unpack(&ptr, 4);
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msg->tpc_command = (rar_tpc_command_t) bit_unpack(&ptr, 3);
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msg->ul_delay = *ptr++;
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msg->csi_req = *ptr++;
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msg->temp_c_rnti = bit_unpack(&ptr, 16);
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ret = LIBLTE_SUCCESS;
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}
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}
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return(ret);
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}
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int main(int argc, char **argv) {
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int ret;
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lte_cell_t cell;
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int64_t sf_cnt;
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ue_mib_t ue_mib;
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void *uhd;
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int n;
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uint8_t bch_payload[BCH_PAYLOAD_LEN], bch_payload_unpacked[BCH_PAYLOAD_LEN];
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uint32_t sfn_offset;
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rar_msg_t rar_msg;
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ra_pusch_t ra_pusch;
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uint32_t rar_window_start = 0, rar_trials = 0, rar_window_stop = 0;
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timestamp_t uhd_time;
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timestamp_t next_tx_time;
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const uint8_t conn_request_msg[] = {0x20, 0x06, 0x1F, 0x5C, 0x2C, 0x04, 0xB2, 0xAC, 0xF6, 0x00, 0x00, 0x00};
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uint8_t data[100];
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parse_args(&prog_args, argc, argv);
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printf("Opening UHD device...\n");
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if (cuhd_open(prog_args.uhd_args, &uhd)) {
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fprintf(stderr, "Error opening uhd\n");
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exit(-1);
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}
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/* Set receiver gain */
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cuhd_set_rx_gain(uhd, prog_args.uhd_gain);
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cuhd_set_tx_gain(uhd, prog_args.uhd_gain);
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//cuhd_set_tx_antenna(uhd, "TX/RX");
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/* set receiver frequency */
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cuhd_set_rx_freq(uhd, (double) prog_args.uhd_rx_freq);
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cuhd_rx_wait_lo_locked(uhd);
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printf("Tunning RX receiver to %.3f MHz\n", (double ) prog_args.uhd_rx_freq/1000000);
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cuhd_set_tx_freq_offset(uhd, prog_args.uhd_tx_freq, prog_args.uhd_tx_freq_offset);
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printf("Tunning TX receiver to %.3f MHz\n", (double ) prog_args.uhd_tx_freq/1000000);
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ret = cuhd_search_and_decode_mib(uhd, &cell_detect_config, prog_args.force_N_id_2, &cell);
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if (ret < 0) {
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fprintf(stderr, "Error searching for cell\n");
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exit(-1);
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} else if (ret == 0) {
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printf("Cell not found\n");
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exit(0);
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}
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/* set sampling frequency */
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int srate = lte_sampling_freq_hz(cell.nof_prb);
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if (srate != -1) {
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cuhd_set_rx_srate(uhd, (double) srate);
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cuhd_set_tx_srate(uhd, (double) srate);
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} else {
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fprintf(stderr, "Invalid number of PRB %d\n", cell.nof_prb);
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exit(-1);
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}
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INFO("Stopping UHD and flushing buffer...\r",0);
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cuhd_stop_rx_stream(uhd);
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cuhd_flush_buffer(uhd);
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if (ue_mib_init(&ue_mib, cell)) {
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fprintf(stderr, "Error initaiting UE MIB decoder\n");
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exit(-1);
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}
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if (prach_init(&prach, lte_symbol_sz(cell.nof_prb), 0, 0, false, 1)) {
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fprintf(stderr, "Error initializing PRACH\n");
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exit(-1);
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}
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prach_buffer_len = prach.N_seq + prach.N_cp;
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for(int i=0;i<NOF_PRACH_SEQUENCES;i++){
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prach_buffers[i] = (cf_t*)malloc(prach_buffer_len*sizeof(cf_t));
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if(!prach_buffers[i]) {
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perror("maloc");
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exit(-1);
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}
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}
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generate_prach_sequences();
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if (ue_ul_init(&ue_ul, cell)) {
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fprintf(stderr, "Error initiating UE UL\n");
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exit(-1);
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}
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pusch_hopping_cfg_t hop_cfg;
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bzero(&hop_cfg, sizeof(pusch_hopping_cfg_t));
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refsignal_drms_pusch_cfg_t drms_cfg;
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bzero(&drms_cfg, sizeof(refsignal_drms_pusch_cfg_t));
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drms_cfg.beta_pusch = 1.0;
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ue_ul_set_pusch_cfg(&ue_ul, &drms_cfg, &hop_cfg);
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cf_t *ul_signal = vec_malloc(sizeof(cf_t) * SF_LEN_PRB(cell.nof_prb));
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if (!ul_signal) {
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perror("malloc");
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exit(-1);
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}
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bzero(ul_signal, sizeof(cf_t) * SF_LEN_PRB(cell.nof_prb));
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state = DECODE_MIB;
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if (ue_sync_init(&ue_sync, cell, cuhd_recv_wrapper_timed, uhd)) {
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fprintf(stderr, "Error initiating ue_sync\n");
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exit(-1);
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}
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if (ue_dl_init(&ue_dl, cell)) {
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fprintf(stderr, "Error initiating UE downlink processing module\n");
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exit(-1);
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}
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/* Initialize subframe counter */
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sf_cnt = 0;
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// Register Ctrl+C handler
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signal(SIGINT, sig_int_handler);
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cuhd_start_rx_stream(uhd);
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struct timeval tdata[3];
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uint16_t ra_rnti;
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/* Main loop */
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while (!go_exit && (sf_cnt < prog_args.nof_subframes || prog_args.nof_subframes == -1)) {
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ret = ue_sync_get_buffer(&ue_sync, &sf_buffer);
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if (ret < 0) {
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fprintf(stderr, "Error calling ue_sync_work()\n");
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}
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/* ue_sync_get_buffer returns 1 if successfully read 1 aligned subframe */
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if (ret == 1) {
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switch (state) {
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case DECODE_MIB:
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if (ue_sync_get_sfidx(&ue_sync) == 0) {
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pbch_decode_reset(&ue_mib.pbch);
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n = ue_mib_decode(&ue_mib, sf_buffer, bch_payload_unpacked, NULL, &sfn_offset);
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if (n < 0) {
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fprintf(stderr, "Error decoding UE MIB\n");
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exit(-1);
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} else if (n == MIB_FOUND) {
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bit_unpack_vector(bch_payload_unpacked, bch_payload, BCH_PAYLOAD_LEN);
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bcch_bch_unpack(bch_payload, BCH_PAYLOAD_LEN, &cell, &sfn);
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printf("Decoded MIB. SFN: %d, offset: %d\n", sfn, sfn_offset);
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sfn = (sfn + sfn_offset)%1024;
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state = SEND_PRACH;
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}
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}
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break;
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case SEND_PRACH:
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if (((sfn%2) == 1) && (ue_sync_get_sfidx(&ue_sync) == 1)) {
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ue_sync_get_last_timestamp(&ue_sync, &uhd_time);
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timestamp_copy(&next_tx_time, &uhd_time);
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timestamp_add(&next_tx_time, 0, 0.01); // send next frame (10 ms)
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printf("Send prach sfn: %d. Last frame time = %.6f, send prach time = %.6f\n",
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sfn, timestamp_real(&uhd_time), timestamp_real(&next_tx_time));
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cuhd_send_timed(uhd, prach_buffers[7], prach_buffer_len,
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next_tx_time.full_secs, next_tx_time.frac_secs);
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ra_rnti = 2;
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rar_window_start = sfn+1;
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rar_window_stop = sfn+3;
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state = RECV_RAR;
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}
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break;
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case RECV_RAR:
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if ((sfn == rar_window_start && ue_sync_get_sfidx(&ue_sync) > 3) || sfn > rar_window_start) {
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gettimeofday(&tdata[1], NULL);
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printf("Looking for RAR in sfn: %d sf_idx: %d\n", sfn, ue_sync_get_sfidx(&ue_sync));
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n = ue_dl_decode_rnti(&ue_dl, sf_buffer, data_rx, ue_sync_get_sfidx(&ue_sync), ra_rnti);
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if (n < 0) {
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fprintf(stderr, "Error decoding UE DL\n");fflush(stdout);
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} else if (n > 0) {
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gettimeofday(&tdata[2], NULL);
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get_time_interval(tdata);
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printf("time exec DL: %d\n",tdata[0].tv_usec);
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gettimeofday(&tdata[1], NULL);
|
|
|
|
rar_unpack(data_rx, &rar_msg);
|
|
rar_msg_fprint(stdout, &rar_msg);
|
|
|
|
dci_rar_to_ra_ul(rar_msg.rba, rar_msg.mcs, rar_msg.hopping_flag, cell.nof_prb, &ra_pusch);
|
|
ra_pusch_fprint(stdout, &ra_pusch, cell.nof_prb);
|
|
|
|
ra_ul_alloc(&ra_pusch.prb_alloc, &ra_pusch, 0, cell.nof_prb);
|
|
|
|
uint32_t ul_sf_idx = (ue_sync_get_sfidx(&ue_sync)+6)%10;
|
|
|
|
ue_ul_set_cfo(&ue_ul, sync_get_cfo(&ue_sync.strack));
|
|
bit_pack_vector((uint8_t*) conn_request_msg, data, ra_pusch.mcs.tbs);
|
|
n = ue_ul_pusch_encode_rnti(&ue_ul, &ra_pusch, data, ul_sf_idx, rar_msg.temp_c_rnti, ul_signal);
|
|
if (n < 0) {
|
|
fprintf(stderr, "Error encoding PUSCH\n");
|
|
exit(-1);
|
|
}
|
|
|
|
gettimeofday(&tdata[2], NULL);
|
|
get_time_interval(tdata);
|
|
printf("time exec UL: %d\n",tdata[0].tv_usec);
|
|
|
|
gettimeofday(&tdata[1], NULL);
|
|
cuhd_stop_rx_stream(uhd);
|
|
cuhd_flush_buffer(uhd);
|
|
gettimeofday(&tdata[2], NULL);
|
|
get_time_interval(tdata);
|
|
printf("time to stop RX: %d\n",tdata[0].tv_usec);
|
|
|
|
ue_sync_get_last_timestamp(&ue_sync, &uhd_time);
|
|
|
|
uint32_t n_ta = lte_N_ta_new_rar(rar_msg.timing_adv_cmd);
|
|
printf("ta: %d, n_ta: %d\n", rar_msg.timing_adv_cmd, n_ta);
|
|
float time_adv_sec = ((float) n_ta)*TS_PRB(cell.nof_prb);
|
|
|
|
vec_sc_prod_cfc(ul_signal, 2, ul_signal, SF_LEN_PRB(cell.nof_prb));
|
|
|
|
timestamp_copy(&next_tx_time, &uhd_time);
|
|
|
|
timestamp_add(&next_tx_time, 0, 0.006 - time_adv_sec); // send after 6 sub-frames (6 ms)
|
|
printf("Send %d samples PUSCH sfn: %d. Last frame time = %.6f"
|
|
"send PUSCH time = %.6f TA: %.1f us\n",
|
|
SF_LEN_PRB(cell.nof_prb), sfn, timestamp_real(&uhd_time),
|
|
timestamp_real(&next_tx_time), time_adv_sec*1000000);
|
|
cuhd_send_timed(uhd, ul_signal, SF_LEN_PRB(cell.nof_prb),
|
|
next_tx_time.full_secs, next_tx_time.frac_secs);
|
|
|
|
go_exit = 1;
|
|
}
|
|
if (sfn >= rar_window_stop) {
|
|
state = SEND_PRACH;
|
|
rar_trials++;
|
|
if (rar_trials >= 4) {
|
|
go_exit = 1;
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
if (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",
|
|
sync_get_peak_value(&ue_sync.sfind),
|
|
ue_sync.frame_total_cnt, ue_sync.state);
|
|
}
|
|
|
|
sf_cnt++;
|
|
} // Main loop
|
|
|
|
ue_dl_free(&ue_dl);
|
|
ue_sync_free(&ue_sync);
|
|
|
|
ue_mib_free(&ue_mib);
|
|
cuhd_close(uhd);
|
|
printf("\nBye\n");
|
|
exit(0);
|
|
}
|
|
|
|
|
|
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|
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