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Diffstat (limited to 'gnuradio-examples/python/hier/digital/receive_path.py')
| -rw-r--r-- | gnuradio-examples/python/hier/digital/receive_path.py | 256 |
1 files changed, 0 insertions, 256 deletions
diff --git a/gnuradio-examples/python/hier/digital/receive_path.py b/gnuradio-examples/python/hier/digital/receive_path.py deleted file mode 100644 index 917ed1aa33..0000000000 --- a/gnuradio-examples/python/hier/digital/receive_path.py +++ /dev/null @@ -1,256 +0,0 @@ -#!/usr/bin/env python -# -# Copyright 2005,2006,2007 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, gru, blks2 -from gnuradio import usrp -from gnuradio import eng_notation -import copy -import sys - -# from current dir -from pick_bitrate import pick_rx_bitrate - -# ///////////////////////////////////////////////////////////////////////////// -# receive path -# ///////////////////////////////////////////////////////////////////////////// - -class receive_path(gr.top_block): - def __init__(self, demod_class, rx_callback, options): - gr.top_block.__init__(self, "receive_path") - options = copy.copy(options) # make a copy so we can destructively modify - - self._verbose = options.verbose - self._rx_freq = options.rx_freq # receiver's center frequency - self._rx_gain = options.rx_gain # receiver's gain - self._rx_subdev_spec = options.rx_subdev_spec # daughterboard to use - self._bitrate = options.bitrate # desired bit rate - self._decim = options.decim # Decimating rate for the USRP (prelim) - self._samples_per_symbol = options.samples_per_symbol # desired samples/symbol - self._fusb_block_size = options.fusb_block_size # usb info for USRP - self._fusb_nblocks = options.fusb_nblocks # usb info for USRP - - self._rx_callback = rx_callback # this callback is fired when there's a packet available - self._demod_class = demod_class # the demodulator_class we're using - - if self._rx_freq is None: - sys.stderr.write("-f FREQ or --freq FREQ or --rx-freq FREQ must be specified\n") - raise SystemExit - - # Set up USRP source; also adjusts decim, samples_per_symbol, and bitrate - self._setup_usrp_source() - - g = self.subdev.gain_range() - if options.show_rx_gain_range: - print "Rx Gain Range: minimum = %g, maximum = %g, step size = %g" \ - % (g[0], g[1], g[2]) - - self.set_gain(options.rx_gain) - - self.set_auto_tr(True) # enable Auto Transmit/Receive switching - - # Set RF frequency - ok = self.set_freq(self._rx_freq) - if not ok: - print "Failed to set Rx frequency to %s" % (eng_notation.num_to_str(self._rx_freq)) - raise ValueError, eng_notation.num_to_str(self._rx_freq) - - # copy the final answers back into options for use by demodulator - options.samples_per_symbol = self._samples_per_symbol - options.bitrate = self._bitrate - options.decim = self._decim - - # Get demod_kwargs - demod_kwargs = self._demod_class.extract_kwargs_from_options(options) - - # Design filter to get actual channel we want - sw_decim = 1 - chan_coeffs = gr.firdes.low_pass (1.0, # gain - sw_decim * self._samples_per_symbol, # sampling rate - 1.0, # midpoint of trans. band - 0.5, # width of trans. band - gr.firdes.WIN_HANN) # filter type - - # Decimating channel filter - # complex in and out, float taps - self.chan_filt = gr.fft_filter_ccc(sw_decim, chan_coeffs) - #self.chan_filt = gr.fir_filter_ccf(sw_decim, chan_coeffs) - # receiver - self.packet_receiver = \ - blks2.demod_pkts(self._demod_class(**demod_kwargs), - access_code=None, - callback=self._rx_callback, - threshold=-1) - - # Carrier Sensing Blocks - alpha = 0.001 - thresh = 30 # in dB, will have to adjust - self.probe = gr.probe_avg_mag_sqrd_c(thresh,alpha) - - # Display some information about the setup - if self._verbose: - self._print_verbage() - - self.channel_filter = gr.fft_filter_ccc(sw_decim, chan_coeffs) - - # connect the channel input filter to the carrier power detector - self.connect(self.u, self.channel_filter, self.probe) - - # connect channel filter to the packet receiver - self.connect(self.channel_filter, self.packet_receiver) - - - def _setup_usrp_source(self): - self.u = usrp.source_c (fusb_block_size=self._fusb_block_size, - fusb_nblocks=self._fusb_nblocks) - adc_rate = self.u.adc_rate() - - # derive values of bitrate, samples_per_symbol, and decim from desired info - (self._bitrate, self._samples_per_symbol, self._decim) = \ - pick_rx_bitrate(self._bitrate, self._demod_class.bits_per_symbol(), \ - self._samples_per_symbol, self._decim, adc_rate) - - self.u.set_decim_rate(self._decim) - - # determine the daughterboard subdevice we're using - if self._rx_subdev_spec is None: - self._rx_subdev_spec = usrp.pick_rx_subdevice(self.u) - self.subdev = usrp.selected_subdev(self.u, self._rx_subdev_spec) - - self.u.set_mux(usrp.determine_rx_mux_value(self.u, self._rx_subdev_spec)) - - def set_freq(self, target_freq): - """ - Set the center frequency we're interested in. - - @param target_freq: frequency in Hz - @rypte: 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 up converter. - """ - r = self.u.tune(0, self.subdev, target_freq) - if r: - return True - - return False - - def set_gain(self, gain): - """ - Sets the analog gain in the USRP - """ - if gain is None: - r = self.subdev.gain_range() - gain = (r[0] + r[1])/2 # set gain to midpoint - self.gain = gain - return self.subdev.set_gain(gain) - - def set_auto_tr(self, enable): - return self.subdev.set_auto_tr(enable) - - def bitrate(self): - return self._bitrate - - def samples_per_symbol(self): - return self._samples_per_symbol - - def decim(self): - return self._decim - - def carrier_sensed(self): - """ - Return True if we think carrier is present. - """ - #return self.probe.level() > X - return self.probe.unmuted() - - def carrier_threshold(self): - """ - Return current setting in dB. - """ - return self.probe.threshold() - - def set_carrier_threshold(self, threshold_in_db): - """ - Set carrier threshold. - - @param threshold_in_db: set detection threshold - @type threshold_in_db: float (dB) - """ - self.probe.set_threshold(threshold_in_db) - - - def add_options(normal, expert): - """ - Adds receiver-specific options to the Options Parser - """ - add_freq_option(normal) - if not normal.has_option("--bitrate"): - normal.add_option("-r", "--bitrate", type="eng_float", default=None, - help="specify bitrate. samples-per-symbol and interp/decim will be derived.") - normal.add_option("-R", "--rx-subdev-spec", type="subdev", default=None, - help="select USRP Rx side A or B") - normal.add_option("", "--rx-gain", type="eng_float", default=None, metavar="GAIN", - help="set receiver gain in dB [default=midpoint]. See also --show-rx-gain-range") - normal.add_option("", "--show-rx-gain-range", action="store_true", default=False, - help="print min and max Rx gain available on selected daughterboard") - normal.add_option("-v", "--verbose", action="store_true", default=False) - expert.add_option("-S", "--samples-per-symbol", type="int", default=None, - help="set samples/symbol [default=%default]") - expert.add_option("", "--rx-freq", type="eng_float", default=None, - help="set Rx frequency to FREQ [default=%default]", metavar="FREQ") - expert.add_option("-d", "--decim", type="intx", default=None, - help="set fpga decimation rate to DECIM [default=%default]") - expert.add_option("", "--log", action="store_true", default=False, - help="Log all parts of flow graph to files (CAUTION: lots of data)") - - # Make a static method to call before instantiation - add_options = staticmethod(add_options) - - - def _print_verbage(self): - """ - Prints information about the receive path - """ - print "\nReceive Path:" - print "Using RX d'board %s" % (self.subdev.side_and_name(),) - print "Rx gain: %g" % (self.gain,) - print "modulation: %s" % (self._demod_class.__name__) - print "bitrate: %sb/s" % (eng_notation.num_to_str(self._bitrate)) - print "samples/symbol: %3d" % (self._samples_per_symbol) - print "decim: %3d" % (self._decim) - print "Rx Frequency: %s" % (eng_notation.num_to_str(self._rx_freq)) - -def add_freq_option(parser): - """ - Hackery that has the -f / --freq option set both tx_freq and rx_freq - """ - def freq_callback(option, opt_str, value, parser): - parser.values.rx_freq = value - parser.values.tx_freq = value - - if not parser.has_option('--freq'): - parser.add_option('-f', '--freq', type="eng_float", - action="callback", callback=freq_callback, - help="set Tx and/or Rx frequency to FREQ [default=%default]", - metavar="FREQ") |