From 23dcd6d927f966d617ec720d770dad87d505f257 Mon Sep 17 00:00:00 2001 From: ismagom Date: Tue, 14 Oct 2014 13:48:01 +0100 Subject: [PATCH] Added cell measurement example --- lte/phy/examples/cell_measurement.c | 218 ++++++++++++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 lte/phy/examples/cell_measurement.c diff --git a/lte/phy/examples/cell_measurement.c b/lte/phy/examples/cell_measurement.c new file mode 100644 index 000000000..1e2baf724 --- /dev/null +++ b/lte/phy/examples/cell_measurement.c @@ -0,0 +1,218 @@ +/** + * + * \section COPYRIGHT + * + * Copyright 2013-2014 The libLTE Developers. See the + * COPYRIGHT file at the top-level directory of this distribution. + * + * \section LICENSE + * + * This file is part of the libLTE library. + * + * libLTE is free software: you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation, either version 3 of + * the License, or (at your option) any later version. + * + * libLTE 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 Lesser General Public License for more details. + * + * A copy of the GNU Lesser 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "liblte/phy/phy.h" +#include "liblte/cuhd/cuhd.h" +#include "cell_search_utils.h" + +/********************************************************************** + * Program arguments processing + ***********************************************************************/ +typedef struct { + int nof_subframes; + bool disable_plots; + int force_N_id_2; + char *uhd_args; + float uhd_freq; + float uhd_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->uhd_args = ""; + args->uhd_freq = -1.0; + args->uhd_gain = 60.0; +} + +void usage(prog_args_t *args, char *prog) { + printf("Usage: %s [aglnv] -f rx_frequency (in Hz)\n", prog); + printf("\t-a UHD args [Default %s]\n", args->uhd_args); + printf("\t-g UHD RX gain [Default %.2f dB]\n", args->uhd_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 verbose to debug, default none]\n"); +} + +void 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->uhd_args = argv[optind]; + break; + case 'g': + args->uhd_gain = atof(argv[optind]); + break; + case 'f': + args->uhd_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': + verbose++; + break; + default: + usage(args, argv[0]); + exit(-1); + } + } + if (args->uhd_freq < 0) { + usage(args, argv[0]); + exit(-1); + } +} +/**********************************************************************/ + +/* TODO: Do something with the output data */ +char data[10000]; + +int cuhd_recv_wrapper(void *h, void *data, uint32_t nsamples) { + DEBUG(" ---- Receive %d samples ---- \n", nsamples); + return cuhd_recv(h, data, nsamples, 1); +} + + +int main(int argc, char **argv) { + int ret; + cf_t *sf_buffer; + prog_args_t prog_args; + lte_cell_t cell; + int64_t sf_cnt; + pbch_mib_t mib; + ue_sync_t ue_sync; + void *uhd; + + parse_args(&prog_args, argc, argv); + + printf("Opening UHD device...\n"); + if (cuhd_open(prog_args.uhd_args, &uhd)) { + fprintf(stderr, "Error opening uhd\n"); + exit(-1); + } + /* Set receiver gain */ + cuhd_set_rx_gain(uhd, prog_args.uhd_gain); + + /* set receiver frequency */ + cuhd_set_rx_freq(uhd, (double) prog_args.uhd_freq); + cuhd_rx_wait_lo_locked(uhd); + printf("Tunning receiver to %.3f MHz\n", (double ) prog_args.uhd_freq/1000000); + + if (cell_search(uhd, prog_args.force_N_id_2, &cell, &mib)) { + fprintf(stderr, "Cell not found\n"); + exit(-1); + } + + cuhd_start_rx_stream(uhd); + + if (ue_sync_init(&ue_sync, cell, cuhd_recv_wrapper, uhd)) { + fprintf(stderr, "Error initiating ue_sync\n"); + exit(-1); + } + + /* Initialize subframe counter */ + sf_cnt = 0; + + lte_fft_t fft; + chest_t chest; + + if (lte_fft_init(&fft, cell.cp, cell.nof_prb)) { + fprintf(stderr, "Error initiating FFT\n"); + return -1; + } + if (chest_init_LTEDL(&chest, cell)) { + fprintf(stderr, "Error initiating channel estimator\n"); + return -1; + } + + int sf_re = SF_LEN_RE(cell.nof_prb, cell.cp); + cf_t *sf_symbols = vec_malloc(sf_re * sizeof(cf_t)); + unsigned int nframes=0; + + /* Main loop */ + while (sf_cnt < prog_args.nof_subframes || prog_args.nof_subframes == -1) { + + ret = ue_sync_get_buffer(&ue_sync, &sf_buffer); + if (ret < 0) { + fprintf(stderr, "Error calling ue_sync_work()\n"); + } + + float rssi=0, rsrp=0, rsrq=0; + + /* iodev_receive returns 1 if successfully read 1 aligned subframe */ + if (ret == 1) { + + /* Run FFT for all subframe data */ + lte_fft_run_sf(&fft, sf_buffer, sf_symbols); + + chest_measure_sf(&chest, sf_symbols, ue_sync_get_sfidx(&ue_sync)); + rssi = VEC_CMA(chest_rssi_sf(&chest, sf_symbols),rssi,nframes); + rsrq = VEC_CMA(chest_rsrq_sf(&chest, sf_symbols, ue_sync_get_sfidx(&ue_sync)),rsrq,nframes); + rsrp = VEC_CMA(chest_rsrp_sf(&chest, ue_sync_get_sfidx(&ue_sync)),rsrp,nframes); + nframes++; + + // Plot and Printf + if ((nframes%10) == 0) { + printf("CFO: %+6.4f KHz, SFO: %+6.4f Khz, RSSI: %+5.2f dBm, RSRP: %+4.2f dBm, RSRQ: %4.2f dB\r", + ue_sync_get_cfo(&ue_sync)/1000, ue_sync_get_sfo(&ue_sync)/1000, + 10*log10(rssi*1000/4/cell.nof_prb/12/2)-prog_args.uhd_gain, + 10*log10(rsrp*1000)-prog_args.uhd_gain, + 10*log10(rsrq)); + } + + } 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_sync_free(&ue_sync); + cuhd_close(uhd); + printf("\nBye\n"); + exit(0); +} + + +