/usr/bin/uhd_rx_nogui is in gnuradio 3.7.2.1-5.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 | #!/usr/bin/python2
#!/usr/bin/env python
#
# Copyright 2006,2007,2011,2012 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, uhd, audio
from gnuradio import filter
from gnuradio import analog
from gnuradio import eng_notation
from gnuradio.eng_option import eng_option
from optparse import OptionParser
import sys
"""
This example application demonstrates receiving and demodulating
different types of signals using the USRP.
A receive chain is built up of the following signal processing
blocks:
USRP - Daughter board source generating complex baseband signal.
CHAN - Low pass filter to select channel bandwidth
RFSQL - RF squelch zeroing output when input power below threshold
AGC - Automatic gain control leveling signal at [-1.0, +1.0]
DEMOD - Demodulation block appropriate to selected signal type.
This converts the complex baseband to real audio frequencies,
and applies an appropriate low pass decimating filter.
CTCSS - Optional tone squelch zeroing output when tone is not present.
RSAMP - Resampler block to convert audio sample rate to user specified
sound card output rate.
AUDIO - Audio sink for playing final output to speakers.
The following are required command line parameters:
-f FREQ USRP receive frequency
-m MOD Modulation type, select from AM, FM, or WFM
The following are optional command line parameters:
-R SUBDEV Daughter board specification, defaults to first found
-c FREQ Calibration offset. Gets added to receive frequency.
Defaults to 0.0 Hz.
-g GAIN Daughterboard gain setting. Defaults to mid-range.
-o RATE Sound card output rate. Defaults to 32000. Useful if
your sound card only accepts particular sample rates.
-r RFSQL RF squelch in db. Defaults to -50.0.
-p FREQ CTCSS frequency. Opens squelch when tone is present.
Once the program is running, ctrl-break (Ctrl-C) stops operation.
Please see fm_demod.py and am_demod.py for details of the demodulation
blocks.
"""
# (device_rate, channel_rate, audio_rate, channel_pass, channel_stop, demod)
demod_params = {
'AM' : (256e3, 16e3, 16e3, 5000, 8000, analog.demod_10k0a3e_cf),
'FM' : (256e3, 32e3, 8e3, 8000, 9000, analog.demod_20k0f3e_cf),
'WFM' : (320e3, 320e3, 32e3, 80000, 115000, analog.demod_200kf3e_cf)
}
class uhd_src(gr.hier_block2):
"""
Create a UHD source object supplying complex floats.
Selects user supplied subdevice or chooses first available one.
Calibration value is the offset from the tuned frequency to
the actual frequency.
"""
def __init__(self, args, spec, antenna, samp_rate, gain=None, calibration=0.0):
gr.hier_block2.__init__(self, "uhd_src",
gr.io_signature(0, 0, 0), # Input signature
gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
self._src = uhd.usrp_source(device_addr=args, stream_args=uhd.stream_args('fc32'))
# Set the subdevice spec
if(spec):
self._src.set_subdev_spec(spec, 0)
# Set the antenna
if(antenna):
self._src.set_antenna(antenna, 0)
self._src.set_samp_rate(samp_rate)
dev_rate = self._src.get_samp_rate()
self._samp_rate = samp_rate
# Resampler to get to exactly samp_rate no matter what dev_rate is
self._rrate = samp_rate / dev_rate
self._resamp = filter.pfb.arb_resampler_ccf(self._rrate)
# If no gain specified, set to midrange
gain_range = self._src.get_gain_range()
if gain is None:
gain = (gain_range.start()+gain_range.stop())/2.0
print "Using gain: ", gain
self._src.set_gain(gain)
self._cal = calibration
self.connect(self._src, self._resamp, self)
def tune(self, freq):
r = self._src.set_center_freq(freq+self._cal, 0)
def rate(self):
return self._samp_rate
class app_top_block(gr.top_block):
def __init__(self, options):
gr.top_block.__init__(self)
self.options = options
(dev_rate, channel_rate, audio_rate,
channel_pass, channel_stop, demod) = demod_params[options.modulation]
DEV = uhd_src(options.args, # UHD device address
options.spec, # device subdev spec
options.antenna, # device antenna
dev_rate, # device sample rate
options.gain, # Receiver gain
options.calibration) # Frequency offset
DEV.tune(options.frequency)
if_rate = DEV.rate()
channel_decim = int(if_rate // channel_rate)
audio_decim = int(channel_rate // audio_rate)
CHAN_taps = filter.optfir.low_pass(1.0, # Filter gain
if_rate, # Sample rate
channel_pass, # One sided modulation bandwidth
channel_stop, # One sided channel bandwidth
0.1, # Passband ripple
60) # Stopband attenuation
CHAN = filter.freq_xlating_fir_filter_ccf(channel_decim, # Decimation rate
CHAN_taps, # Filter taps
0.0, # Offset frequency
if_rate) # Sample rate
RFSQL = analog.pwr_squelch_cc(options.rf_squelch, # Power threshold
125.0/channel_rate, # Time constant
int(channel_rate/20), # 50ms rise/fall
False) # Zero, not gate output
AGC = analog.agc_cc(1.0/channel_rate, # Time constant
1.0, # Reference power
1.0, # Initial gain
1.0) # Maximum gain
DEMOD = demod(channel_rate, audio_decim)
# From RF to audio
#self.connect(DEV, CHAN, RFSQL, AGC, DEMOD)
self.connect(DEV, CHAN, DEMOD)
# Optionally add CTCSS and RSAMP if needed
tail = DEMOD
if options.ctcss != None and options.ctcss > 60.0:
CTCSS = analog.ctcss_squelch_ff(audio_rate, # Sample rate
options.ctcss) # Squelch tone
self.connect(DEMOD, CTCSS)
tail = CTCSS
if options.output_rate != audio_rate:
out_lcm = gru.lcm(audio_rate, options.output_rate)
out_interp = int(out_lcm // audio_rate)
out_decim = int(out_lcm // options.output_rate)
RSAMP = filter.rational_resampler_fff(out_interp, out_decim)
self.connect(tail, RSAMP)
tail = RSAMP
# Send to audio output device
AUDIO = audio.sink(int(options.output_rate),
options.audio_output)
self.connect(tail, AUDIO)
# Direct asynchronous notifications to callback function
if self.options.show_async_msg:
self.async_msgq = gr.msg_queue(0)
self.async_src = uhd.amsg_source("", self.async_msgq)
self.async_rcv = gru.msgq_runner(self.async_msgq, self.async_callback)
def async_callback(self, msg):
md = self.async_src.msg_to_async_metadata_t(msg)
print "Channel: %i Time: %f Event: %i" % (md.channel, md.time_spec.get_real_secs(), md.event_code)
def main():
parser = OptionParser(option_class=eng_option)
parser.add_option("-a", "--args", type="string", default="",
help="UHD device address args , [default=%default]")
parser.add_option("", "--spec", type="string", default=None,
help="Subdevice of UHD device where appropriate")
parser.add_option("-A", "--antenna", type="string", default=None,
help="select Rx Antenna where appropriate [default=%default]")
parser.add_option("-f", "--frequency", type="eng_float",
default=None, metavar="Hz",
help="set receive frequency to Hz [default=%default]")
parser.add_option("-c", "--calibration", type="eng_float",
default=0.0, metavar="Hz",
help="set frequency offset to Hz [default=%default]")
parser.add_option("-g", "--gain", type="eng_float",
metavar="dB", default=None,
help="set RF gain [default is midpoint]")
parser.add_option("-m", "--modulation", type="choice", choices=('AM','FM','WFM'),
metavar="TYPE", default=None,
help="set modulation type (AM,FM,WFM) [default=%default]")
parser.add_option("-o", "--output-rate", type="eng_float",
default=32000, metavar="RATE",
help="set audio output rate to RATE [default=%default]")
parser.add_option("-r", "--rf-squelch", type="eng_float",
default=-50.0, metavar="dB",
help="set RF squelch to dB [default=%default]")
parser.add_option("-p", "--ctcss", type="float",
default=None, metavar="FREQ",
help="set CTCSS squelch to FREQ [default=%default]")
parser.add_option("-O", "--audio-output", type="string", default="default",
help="pcm device name. E.g., hw:0,0 or surround51 or /dev/dsp")
parser.add_option("", "--show-async-msg", action="store_true", default=False,
help="Show asynchronous message notifications from UHD [default=%default]")
(options, args) = parser.parse_args()
if options.frequency is None:
sys.stderr.write("Must supply receive frequency with -f.\n")
sys.exit(1)
if options.modulation is None:
sys.stderr.write("Must supply a modulation type (AM, FM, WFM).\n")
sys.exit(1)
tb = app_top_block(options)
try:
tb.run()
except KeyboardInterrupt:
pass
if __name__ == "__main__":
main()
|