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#!/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']:
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 = 64e6
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)
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")
(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()
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