Hacking:Gsm receive rtl.py

#!/usr/bin/env python

from gnuradio import gr, gru, blks2
#, gsm
from gnuradio.eng_option import eng_option
from optparse import OptionParser
from os import sys

for extdir in ['../../debug/src/lib','../../debug/src/lib/.libs','../lib','../lib/.libs']:
    if extdir not in sys.path:
        sys.path.append(extdir)
import gsm

class tuner(gr.feval_dd):
    def __init__(self, top_block):
        gr.feval_dd.__init__(self)
        self.top_block = top_block
    def eval(self, freq_offet):
        self.top_block.set_center_frequency(freq_offet)
        return freq_offet

class synchronizer(gr.feval_dd):
    def __init__(self, top_block):
        gr.feval_dd.__init__(self)
        self.top_block = top_block

    def eval(self, timing_offset):
        self.top_block.set_timing(timing_offset)
        return freq_offet

class gsm_receiver_first_blood(gr.top_block):
    def __init__(self):
        gr.top_block.__init__(self)
        (options, args) = self._process_options()
        self.tuner_callback = tuner(self)
        self.synchronizer_callback = synchronizer(self)
        self.options    = options
        self.args       = args
        self._set_rates()
        self.source = self._set_source()
        self.filtr = self._set_filter()
        self.interpolator = self._set_interpolator()
        self.receiver = self._set_receiver()
        self.converter = self._set_converter()
        self.sink = self._set_sink()
    
        self.connect(self.source, self.filtr,  self.interpolator, self.receiver, self.converter, self.sink)
  
    def _set_sink(self):
        nazwa_pliku_wy = self.options.outputfile
        ujscie = gr.file_sink(gr.sizeof_float, nazwa_pliku_wy)
        return ujscie
    
    def _set_source(self):
        nazwa_pliku = self.options.inputfile
        zrodlo = gr.file_source(gr.sizeof_gr_complex, nazwa_pliku, False)
        return zrodlo
    
    def _set_rates(self):
        options = self.options
        clock_rate = 2285712
        self.clock_rate = clock_rate
        self.input_rate = clock_rate / options.decim
        self.gsm_symb_rate = 1625000.0 / 6.0
        self.sps = self.input_rate / self.gsm_symb_rate / self.options.osr

    def _set_filter(self):
        filter_cutoff   = 145e3	
        filter_t_width  = 10e3
        offset = 0
        print "input_rate:", self.input_rate, "sample rate:", self.sps, " filter_cutoff:", filter_cutoff, " filter_t_width:", filter_t_width
        filter_taps     = gr.firdes.low_pass(1.0, self.input_rate, filter_cutoff, filter_t_width, gr.firdes.WIN_HAMMING)
        filtr          = gr.freq_xlating_fir_filter_ccf(1, filter_taps, offset, self.input_rate)
        return filtr

    def _set_converter(self):
        v2s = gr.vector_to_stream(gr.sizeof_float, 142)
        return v2s
    
    def _set_interpolator(self):
        interpolator = gr.fractional_interpolator_cc(0, self.sps) 
        return interpolator
    
    def _set_receiver(self):
        receiver = gsm.receiver_cf(self.tuner_callback, self.synchronizer_callback, self.options.osr, self.options.key.replace(' ', '').lower(), self.options.configuration.upper())
        return receiver
    
    def _process_options(self):
        parser = OptionParser(option_class=eng_option)
        parser.add_option("-d", "--decim", type="int", default=128,
                          help="Set USRP decimation rate to DECIM [default=%default]")
        parser.add_option("-r", "--osr", type="int", default=4,
                          help="Oversampling ratio [default=%default]")
        parser.add_option("-I", "--inputfile", type="string", default="cfile",
                          help="Input filename")
        parser.add_option("-O", "--outputfile", type="string", default="cfile2.out",
                          help="Output filename")
        parser.add_option("-k", "--key", type="string", default="AD 6A 3E C2 B4 42 E4 00",
                          help="KC session key")
        parser.add_option("-c", "--configuration", type="string", default="",
                          help="Decoder configuration")

        (options, args) = parser.parse_args ()
        return (options, args)
    
    def set_center_frequency(self, center_freq):
        self.filtr.set_center_freq(center_freq)

    def set_timing(self, timing_offset):
        pass

def main():
    try:
        gsm_receiver_first_blood().run()
    except KeyboardInterrupt:
        pass

if __name__ == '__main__':
    main()