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Diffstat (limited to 'apps/helpers/grgsm_channelize')
-rwxr-xr-x | apps/helpers/grgsm_channelize | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/apps/helpers/grgsm_channelize b/apps/helpers/grgsm_channelize new file mode 100755 index 0000000..fb30334 --- /dev/null +++ b/apps/helpers/grgsm_channelize @@ -0,0 +1,168 @@ +#!/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)) + +def gsm_band(value): + choices = arfcn.get_bands() + if value in choices: + return value + else: + raise ArgumentTypeError("invalid GSM band: {0}. Possible choices are: {1}".format(value, choices)) + +class grgsm_channelize(gr.top_block): + def __init__(self, channels, resamp_rate, fc, band, samp_rate, input_file, dest_dir, data_type="complex"): + gr.top_block.__init__(self, "grgsm_channelize") + + ################################################## + # Parameters + ################################################## + self.channels = channels + self.resamp_rate = resamp_rate + self.fc = fc + self.band = band + 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 == "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(channels), eng_notation.num_to_str(fc))) + + for channel in channels: + channel_freq = arfcn.arfcn2downlink(channel, band) + if channel_freq is None: + print("Warning: invalid ARFCN %d for band %s" % (channel, band)) + continue + 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="channel", type=int, nargs='+', + help="List of ARFCNs") + 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("-b", "--band", dest="band", type=gsm_band, default='E-GSM', + help="GSM band [default=%(default)s]") #TODO: add automatic discovery based on fc + 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"], 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() + + 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(channels=args.channel, + resamp_rate=resamp_rate, + fc=args.fc, + band=args.band, + 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!") |