diff options
Diffstat (limited to 'gnuradio-examples/python/dect')
| -rw-r--r-- | gnuradio-examples/python/dect/Makefile.am | 33 | ||||
| -rw-r--r-- | gnuradio-examples/python/dect/README | 46 | ||||
| -rw-r--r-- | gnuradio-examples/python/dect/dect_receiver.py | 80 | ||||
| -rwxr-xr-x | gnuradio-examples/python/dect/usrp_dect.py | 62 | ||||
| -rw-r--r-- | gnuradio-examples/python/dect/usrp_source.py | 124 |
5 files changed, 345 insertions, 0 deletions
diff --git a/gnuradio-examples/python/dect/Makefile.am b/gnuradio-examples/python/dect/Makefile.am new file mode 100644 index 000000000..c65bd4c42 --- /dev/null +++ b/gnuradio-examples/python/dect/Makefile.am @@ -0,0 +1,33 @@ +# +# 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. +# + +include $(top_srcdir)/Makefile.common + +EXTRA_DIST = \ + README \ + dect_receiver.py \ + usrp_source.py \ + usrp_dect.py + +ourdatadir = $(exampledir)/dect +ourdata_DATA = $(EXTRA_DIST) + +MOSTLYCLEANFILES = *.pyc *~ diff --git a/gnuradio-examples/python/dect/README b/gnuradio-examples/python/dect/README new file mode 100644 index 000000000..c8853f185 --- /dev/null +++ b/gnuradio-examples/python/dect/README @@ -0,0 +1,46 @@ +This directory contains a work in progress service monitor for DECT +digital cordless phone base stations and handsets. + + +Status +------ + +2007 Apr 27 - Converted to new hier_block2 format +2007 Apr 03 - Development on hold. +2007 Feb 11 - Added GMSK demodulation and option to log to file +2007 Feb 10 - Able to tune and log filtered baseband to file + + +Files +----- + +usrp_dect.py - DECT receiver application + +dect_receiver.py - Top-level hierarchical block (new type) implementing + receiver + +usrp_source.py - Hierarchical block (new type) implementing a USRP + complex source, with convenience functions for tuning, + gain, decimation, etc. + +gmsk2.py - Hierarchical block (new type) implementing GMSK + modulation and demodulation. This will eventually go + into the core blksimpl directory + +DECT Modulation Details +----------------------- + +In the US, the FCC has allocated four carrier frequencies for DECT usage: + +Channel Frequency +------- --------- + 1 1921.536 MHz + 2 1923.264 MHz + 3 1924.992 MHz + 4 1926.720 MHz + +These are spaced at 1.728 MHz intervals. + +The DECT PHY uses GMSK with a 0.5 bandwidth-time product at 1.152 Msym/sec, +for an occupied bandwidth (99% power) of 1.186 MHz (1.03 x symbol rate.) + diff --git a/gnuradio-examples/python/dect/dect_receiver.py b/gnuradio-examples/python/dect/dect_receiver.py new file mode 100644 index 000000000..89e60c949 --- /dev/null +++ b/gnuradio-examples/python/dect/dect_receiver.py @@ -0,0 +1,80 @@ +#!/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) diff --git a/gnuradio-examples/python/dect/usrp_dect.py b/gnuradio-examples/python/dect/usrp_dect.py new file mode 100755 index 000000000..27259d812 --- /dev/null +++ b/gnuradio-examples/python/dect/usrp_dect.py @@ -0,0 +1,62 @@ +#!/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, eng_notation +from gnuradio.eng_option import eng_option +from optparse import OptionParser +from dect_receiver import dect_receiver +import sys + +def main(): + parser = OptionParser(option_class=eng_option) + parser.add_option("-R", "--rx-subdev-spec", type="subdev", default=None, + help="select USRP Rx side A or B (default=first one with a daughterboard)") + parser.add_option("-f", "--freq", type="eng_float", default=None, + help="set frequency to FREQ", metavar="FREQ") + parser.add_option("", "--calibration", type="eng_float", default=0.0, + help="set frequency calibration offset to FREQ") + parser.add_option("-g", "--gain", type="eng_float", default=None, + help="set gain in dB (default is midpoint)") + parser.add_option("-v", "--verbose", action="store_true", default=False, + help="print extra debugging info") + parser.add_option("", "--log-baseband", default=None, + help="log filtered baseband to file") + parser.add_option("", "--log-demod", default=None, + help="log demodulator output to file") + (options, args) = parser.parse_args() + + if len(sys.argv) == 1 or len(args) != 0: + parser.print_help() + sys.exit(1) + + # Create an instance of a hierarchical block + top_block = dect_receiver(options) + + try: + # Run forever + top_block.run() + except KeyboardInterrupt: + # Ctrl-C exits + pass + +if __name__ == '__main__': + main () diff --git a/gnuradio-examples/python/dect/usrp_source.py b/gnuradio-examples/python/dect/usrp_source.py new file mode 100644 index 000000000..6a779840f --- /dev/null +++ b/gnuradio-examples/python/dect/usrp_source.py @@ -0,0 +1,124 @@ +#!/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, usrp, eng_notation +n2s = eng_notation.num_to_str + +# Hierarchical block implementing a USRP source for complex floats, +# with convenience functions for gain, tune, decimation, etc. +# +class usrp_source_c(gr.hier_block2): + """ + Create a USRP source object supplying complex floats. + """ + def __init__(self, which=0, subdev_spec=None, gain=None, if_rate=None, + freq=0.0, calibration=0.0, verbose=False): + # Call hierarchical block constructor + gr.hier_block2.__init__(self, + "usrp_source_c", # Block typename + gr.io_signature(0,0,0), # Input signature + gr.io_signature(1,1,gr.sizeof_gr_complex)) # Output signature + + self._verbose = verbose + self._u = usrp.source_c(which) + if self._verbose: + print 'ADC sample rate is', n2s(self._u.adc_rate()), "sps" + self.set_subdev(subdev_spec) + self.set_if_rate(if_rate) + self.set_gain(gain) + self.set_calibration(calibration) + self.tune(freq) + self.connect(self._u, self) + + def set_subdev(self, subdev_spec): + if subdev_spec is None: + subdev_spec = self.pick_subdevice() + self._subdev = usrp.selected_subdev(self._u, subdev_spec) + self._u.set_mux(usrp.determine_rx_mux_value(self._u, subdev_spec)) + if self._verbose: + print 'RX using', self._subdev.name(), 'daughterboard' + + def pick_subdevice(self): + """ + The user didn't specify a subdevice. + If there's a daughterboard on A, select A. + If there's a daughterboard on B, select B. + Otherwise, select A. + """ + if self._u.db[0][0].dbid() >= 0: # dbid is < 0 if there's no d'board or a problem + return (0, 0) + if self._u.db[1][0].dbid() >= 0: + return (1, 0) + return (0, 0) + + def set_if_rate(self, if_rate): + # If no IF rate specified, set to maximum decimation + if if_rate is None: + self._decim = 256 + else: + self._decim = int(self._u.adc_rate()/if_rate) + + self._u.set_decim_rate(self._decim) + self._if_rate = self._u.adc_rate()/self._decim + + if self._verbose: + print "USRP decimation rate is", self._decim + print "USRP IF rate is", n2s(self._if_rate), "sps" + + def set_gain(self, gain): + # If no gain specified, set to midrange + if gain is None: + g = self._subdev.gain_range() + gain = (g[0]+g[1])/2.0 + self._gain = gain + self._subdev.set_gain(self._gain) + + def set_calibration(self, calibration): + self._cal = calibration + if self._verbose: + print "Using frequency calibration offset of", n2s(calibration), "Hz" + + def tune(self, freq): + """ + Set the center frequency we're interested in. + + @param target_freq: frequency in Hz + @type: bool + + Tuning is a two step process. First we ask the front-end to + tune as close to the desired frequency as it can. Then we use + the result of that operation and our target_frequency to + determine the value for the digital down converter. + """ + self._tune_result = usrp.tune(self._u, 0, self._subdev, freq+self._cal) + if self._tune_result: + if self._verbose: + print "Baseband frequency is", n2s(self._tune_result.baseband_freq), "Hz" + print "DXC frequency is", n2s(self._tune_result.dxc_freq), "Hz" + print "Center frequency is", n2s(freq), "Hz" + print "Residual frequency is", n2s(self._tune_result.residual_freq), "Hz" + return True + + return False + +if __name__ == '__main__': + src = usrp_source_c(verbose=True) |