#!/usr/bin/env python # # Copyright 2004,2005,2007,2013 Free Software Foundation, Inc. # # This file is part of GNU Radio # # GNU Radio 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. # # GNU Radio 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 GNU Radio; see the file COPYING. If not, write to # the Free Software Foundation, Inc., 51 Franklin Street, # Boston, MA 02110-1301, USA. # # Gang - Here's a simple script that demonstrates spectrum inversion # using the multiply by [1,-1] method (mixing with Nyquist frequency). # Requires nothing but a sound card, and sounds just like listening # to a SSB signal on the wrong sideband. # from gnuradio import gr from gnuradio import audio from gnuradio import blocks from gnuradio.eng_arg import eng_float, intx from argparse import ArgumentParser class my_top_block(gr.top_block): def __init__(self): gr.top_block.__init__(self) parser = ArgumentParser() parser.add_argument("-I", "--audio-input", default="", help="pcm input device name. E.g., hw:0,0 or /dev/dsp") parser.add_argument("-O", "--audio-output", default="", help="pcm output device name. E.g., hw:0,0 or /dev/dsp") parser.add_argument("-r", "--sample-rate", type=eng_float, default=8000, help="set sample rate to RATE (%(default)r)") args = parser.parse_args() sample_rate = int(args.sample_rate) src = audio.source (sample_rate, args.audio_input) dst = audio.sink (sample_rate, args.audio_output) vec1 = [1, -1] vsource = blocks.vector_source_f(vec1, True) multiply = blocks.multiply_ff() self.connect(src, (multiply, 0)) self.connect(vsource, (multiply, 1)) self.connect(multiply, dst) if __name__ == '__main__': try: my_top_block().run() except KeyboardInterrupt: pass