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diff --git a/gnuradio-examples/python/dect/dect_receiver.py b/gnuradio-examples/python/dect/dect_receiver.py
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+#!/usr/bin/env python
+#
+# Copyright 2007 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.
+#
+
+from gnuradio import gr, optfir, blks2
+from usrp_source import usrp_source_c
+
+_dect_symbol_rate = 1.152e6
+_dect_occupied_bandwidth = _dect_symbol_rate * 1.03 # BT=0.5
+_dect_channel_bandwidth = 1.728e6
+
+# Top-level hierarchical block that implements DECT demodulation and
+# decoding.
+class dect_receiver(gr.top_block):
+ def __init__(self, options):
+ gr.top_block.__init__(self, "dect_receiver")
+ self._options = options
+
+ # Need greater than 2 samples per symbol. This makes a decimation
+ # rate of 26 and a samples per symbol of 2.136752
+ if_rate = 2.461538e6
+ self._usrp = usrp_source_c(which=0,
+ subdev_spec=options.rx_subdev_spec,
+ if_rate=if_rate,
+ gain=options.gain,
+ freq=options.freq,
+ calibration=options.calibration,
+ verbose=options.verbose)
+
+ # Filter baseband to 1.186 MHz passband, 1.728 MHz stopband
+ chan_taps = optfir.low_pass(1.0, # Gain
+ if_rate, # Sample rate
+ _dect_occupied_bandwidth/2, # One sided modulation bandwidth
+ _dect_channel_bandwidth/2, # One sided channel bandwidth
+ 1.0, # Passband ripple (db)
+ 60) # Stopband attenuation (db)
+ if self._options.verbose:
+ print "Channel filter has", len(chan_taps), "taps"
+ self._channel_filter = gr.freq_xlating_fir_filter_ccf(1, # Decimation rate
+ chan_taps, # Filter taps
+ 0.0, # Offset frequency
+ if_rate) # Sample rate
+
+ self._demod = blks2.gmsk_demod(samples_per_symbol=if_rate/_dect_symbol_rate,
+ verbose=options.verbose)
+
+ self._sink = gr.null_sink(gr.sizeof_char)
+ self.connect(self._usrp, self._channel_filter, self._demod, self._sink)
+
+ # Log baseband to file if requested
+ if options.log_baseband is not None:
+ if options.verbose:
+ print "Logging baseband to file", options.log_baseband
+ self.baseband_log = gr.file_sink(gr.sizeof_gr_complex, options.log_baseband)
+ self.connect(self._channel_filter, self.baseband_log)
+
+ # Log demodulator output to file if requested
+ if options.log_demod is not None:
+ if options.verbose:
+ print "Logging demodulator to file", options.log_demod
+ self.demod_log = gr.file_sink(gr.sizeof_char, options.log_demod)
+ self.connect(self._demod, self.demod_log)