| #!/usr/bin/env python2 |
| # -*- coding: utf-8 -*- |
| # @file |
| # @author (C) 2015 by Pieter Robyns <pieter.robyns@uhasselt.be> |
| # @section LICENSE |
| # |
| # Gr-gsm is free software; you can redistribute it and/or modify |
| # it under the terms of the GNU General Public License as published by |
| # the Free Software Foundation; either version 3, or (at your option) |
| # any later version. |
| # |
| # Gr-gsm 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 General Public License for more details. |
| # |
| # You should have received a copy of the GNU General Public License |
| # along with gr-gsm; see the file COPYING. If not, write to |
| # the Free Software Foundation, Inc., 51 Franklin Street, |
| # Boston, MA 02110-1301, USA. |
| # |
| # |
| |
| ################################################## |
| # gr-gsm channelizer |
| # |
| # Standalone application to channelize a wideband |
| # GSM capture file into multiple seperate capture |
| # files for the specified ARFCNs. |
| ################################################## |
| |
| from gnuradio import blocks |
| from gnuradio import eng_notation |
| from gnuradio import filter |
| from gnuradio import gr |
| from gnuradio.eng_option import eng_option |
| from gnuradio.filter import firdes |
| from argparse import ArgumentParser, ArgumentTypeError, RawDescriptionHelpFormatter |
| import grgsm.arfcn as arfcn |
| from gnuradio.filter import pfb |
| import math |
| import os |
| |
| EXTRA_HELP = """ |
| Example usage: |
| grgsm_channelize.py -c my_wideband_capture.cfile -f 925.2e6 990 991 992 993 994 995 1019 1020 1021 1022 1023 |
| |
| The above example will channelize my_wideband_capture.cfile, in this case a cfile captured at |
| 925.2 MHz centered (ARFCN 975) and 2 Msps. As a result, 12 files will be generated for |
| ARFCNs 975 - 1023 at 1 Msps each. |
| """ |
| |
| def eng_float(value): |
| try: |
| return eng_notation.str_to_num(value) |
| except: |
| raise ArgumentTypeError("invalid engineering notation value: {0}".format(value)) |
| |
| class grgsm_channelize(gr.top_block): |
| def __init__(self, arfcns, resamp_rate, fc, samp_rate, input_file, dest_dir, data_type="complex"): |
| gr.top_block.__init__(self, "grgsm_channelize") |
| |
| ################################################## |
| # Parameters |
| ################################################## |
| self.arfcns = arfcns |
| self.resamp_rate = resamp_rate |
| self.fc = fc |
| self.samp_rate = samp_rate |
| self.blocks_resamplers = {} |
| self.blocks_rotators = {} |
| self.blocks_file_sinks = {} |
| |
| ################################################## |
| # Blocks and connections |
| ################################################## |
| self.source = None |
| if data_type == "ishort": |
| self.blocks_file_source = blocks.file_source(gr.sizeof_short, input_file, False) |
| self.source = blocks.interleaved_short_to_complex(False, False) |
| self.connect((self.blocks_file_source, 0), (self.source, 0)) |
| elif data_type == "ichar": |
| self.blocks_file_source = blocks.file_source(gr.sizeof_char, input_file, False) |
| self.source = blocks.interleaved_char_to_complex(False) |
| self.connect((self.blocks_file_source, 0), (self.source, 0)) |
| elif data_type == "complex": |
| self.source = blocks.file_source(gr.sizeof_gr_complex, input_file, False) |
| |
| fc_str = eng_notation.num_to_str(fc) |
| print("Extracting channels %s, given that the center frequency is at %s" % (str(arfcns), eng_notation.num_to_str(fc))) |
| |
| for channel in self.arfcns: |
| channel_freq = arfcn.arfcn2downlink(channel) |
| freq_diff = channel_freq - fc |
| freq_diff_str = "+" if 0 <= freq_diff else "" |
| freq_diff_str += eng_notation.num_to_str(freq_diff) |
| print("ARFCN %d is at %sHz %sHz" % (channel, fc_str, freq_diff_str)) |
| |
| self.blocks_resamplers[channel] = pfb.arb_resampler_ccf( resamp_rate, taps=None, flt_size=32) |
| self.blocks_rotators[channel] = blocks.rotator_cc(-2*math.pi*(freq_diff)/samp_rate) |
| self.connect( (self.source, 0), (self.blocks_rotators[channel], 0) ) |
| self.connect( (self.blocks_rotators[channel], 0), (self.blocks_resamplers[channel], 0) ) |
| |
| self.blocks_file_sinks[channel] = blocks.file_sink(gr.sizeof_gr_complex, dest_dir+"/out_" + str(channel) + ".cfile", False) |
| self.blocks_file_sinks[channel].set_unbuffered(False) |
| self.connect((self.blocks_resamplers[channel], 0), (self.blocks_file_sinks[channel], 0)) |
| |
| |
| if __name__ == '__main__': |
| parser = ArgumentParser(formatter_class=RawDescriptionHelpFormatter, description='Split wideband a GSM capture into seperate files per ARFCN.', add_help=True, epilog=EXTRA_HELP) |
| parser.add_argument(dest="arfcns", type=int, nargs='+', |
| help="List of ARFCNs (for PCS1900 add 0x8000 (2**15) to the ARFCN number)") |
| parser.add_argument("-s", "--samp-rate", dest="samp_rate", type=eng_float, default=eng_notation.num_to_str(2e6), |
| help="Sample rate of the wideband capture file [default=%(default)s]") |
| parser.add_argument("-f", "--fc", dest="fc", type=eng_float, default=eng_notation.num_to_str(935e6), required=True, |
| help="Carrier frequency in Hz [default=%(default)s]") |
| parser.add_argument("-o", "--out-samp-rate", dest="out_samp_rate", type=eng_float, default=eng_notation.num_to_str(1e6), |
| help="Sample rate of the output capture files [default=%(default)s]") |
| parser.add_argument("-i", "--input_file", dest="input_file", type=str, required=True, |
| help="Path to wideband GSM capture file") |
| parser.add_argument("-t", "--data_type", dest="data_type", type=str, choices=["complex","ishort","ichar"], default="complex", |
| help="Type of the input file [default=%(default)s]") |
| parser.add_argument("-d", "--dest_dir", dest="dest_dir", type=str, |
| help="Destination directory - if not given defaults to input file name without extension") |
| |
| args = parser.parse_args() |
| |
| for ch in args.arfcns: |
| if not arfcn.is_valid_arfcn(ch): |
| parser.error("ARFCN "+str(ch)+" is not valid\n") |
| |
| if not os.path.exists(args.input_file): |
| raise IOError(args.input_file + " does not exist") |
| |
| input_filename, _ = os.path.splitext(os.path.basename(args.input_file)) |
| |
| if args.dest_dir is None: |
| args.dest_dir = input_filename |
| |
| if not os.path.exists("./"+args.dest_dir): |
| os.makedirs("./"+args.dest_dir) |
| |
| |
| if args.samp_rate % args.out_samp_rate != 0: |
| raise Exception("Input sample rate should be multiple of output sample rate in order to get integer decimation.") |
| |
| resamp_rate = args.out_samp_rate / args.samp_rate |
| print("Input sample rate: " + eng_notation.num_to_str(args.samp_rate)) |
| print("Output sample rate: " + eng_notation.num_to_str(args.out_samp_rate)) |
| print("==> using resample rate of " + str(resamp_rate)) |
| |
| tb = grgsm_channelize(arfcns=args.arfcns, |
| resamp_rate=resamp_rate, |
| fc=args.fc, |
| samp_rate=args.samp_rate, |
| input_file=args.input_file, |
| dest_dir=args.dest_dir, |
| data_type=args.data_type |
| ) |
| tb.start() |
| tb.wait() |
| print("Done!") |