mirror of https://gerrit.osmocom.org/osmo-tetra
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
256 lines
7.9 KiB
256 lines
7.9 KiB
#!/usr/bin/env python
|
|
|
|
# Copyright 2012 Dimitri Stolnikov <horiz0n@gmx.net>
|
|
|
|
# Usage:
|
|
# src$ ./demod/python/osmosdr-tetra_demod_fft.py -o /dev/stdout | ./float_to_bits /dev/stdin /dev/stdout | ./tetra-rx /dev/stdin
|
|
#
|
|
# Adjust the center frequency (-f) and gain (-g) according to your needs.
|
|
# Use left click in Wideband Spectrum window to roughly select a TETRA carrier.
|
|
# In Wideband Spectrum you can also tune by 1/4 of the bandwidth by clicking on the rightmost/leftmost spectrum side.
|
|
# Use left click in Channel Spectrum windows to fine tune the carrier by clicking on the left or right side of the spectrum.
|
|
|
|
|
|
import sys
|
|
import math
|
|
from gnuradio import gr, gru, eng_notation, blocks, filter
|
|
from gnuradio.filter import pfb
|
|
from gnuradio.eng_option import eng_option
|
|
from gnuradio.wxgui import fftsink2, scopesink2, forms, TRIG_MODE_AUTO
|
|
from grc_gnuradio import wxgui as grc_wxgui
|
|
from optparse import OptionParser
|
|
import osmosdr
|
|
import wx
|
|
|
|
try:
|
|
import cqpsk
|
|
except:
|
|
from tetra_demod import cqpsk
|
|
|
|
# applies frequency translation, resampling and demodulation
|
|
|
|
class top_block(grc_wxgui.top_block_gui):
|
|
def __init__(self):
|
|
grc_wxgui.top_block_gui.__init__(self, title="Top Block")
|
|
|
|
options = get_options()
|
|
|
|
self.ifreq = options.frequency
|
|
self.rfgain = options.gain
|
|
|
|
self.src = osmosdr.source(options.args)
|
|
self.src.set_center_freq(self.ifreq)
|
|
self.src.set_sample_rate(int(options.sample_rate))
|
|
|
|
if self.rfgain is None:
|
|
self.src.set_gain_mode(1)
|
|
self.iagc = 1
|
|
self.rfgain = 0
|
|
else:
|
|
self.iagc = 0
|
|
self.src.set_gain_mode(0)
|
|
self.src.set_gain(self.rfgain)
|
|
|
|
# may differ from the requested rate
|
|
sample_rate = self.src.get_sample_rate()
|
|
sys.stderr.write("sample rate: %d\n" % (sample_rate))
|
|
|
|
symbol_rate = 18000
|
|
sps = 2 # output rate will be 36,000
|
|
out_sample_rate = symbol_rate * sps
|
|
|
|
options.low_pass = options.low_pass / 2.0
|
|
|
|
if sample_rate == 96000: # FunCube Dongle
|
|
first_decim = 2
|
|
else:
|
|
first_decim = 10
|
|
|
|
self.offset = 0
|
|
|
|
taps = filter.firdes.low_pass(1.0, sample_rate, options.low_pass, options.low_pass * 0.2, filter.firdes.WIN_HANN)
|
|
self.tuner = filter.freq_xlating_fir_filter_ccf(first_decim, taps, self.offset, sample_rate)
|
|
|
|
self.demod = cqpsk.cqpsk_demod(
|
|
samples_per_symbol = sps,
|
|
excess_bw=0.35,
|
|
costas_alpha=0.03,
|
|
gain_mu=0.05,
|
|
mu=0.05,
|
|
omega_relative_limit=0.05,
|
|
log=options.log,
|
|
verbose=options.verbose)
|
|
|
|
self.output = blocks.file_sink(gr.sizeof_float, options.output_file)
|
|
|
|
rerate = float(sample_rate / float(first_decim)) / float(out_sample_rate)
|
|
sys.stderr.write("resampling factor: %f\n" % rerate)
|
|
|
|
if rerate.is_integer():
|
|
sys.stderr.write("using pfb decimator\n")
|
|
self.resamp = pfb.decimator_ccf(int(rerate))
|
|
else:
|
|
sys.stderr.write("using pfb resampler\n")
|
|
self.resamp = pfb.arb_resampler_ccf(1 / rerate)
|
|
|
|
self.connect(self.src, self.tuner, self.resamp, self.demod, self.output)
|
|
|
|
self.Main = wx.Notebook(self.GetWin(), style=wx.NB_TOP)
|
|
self.Main.AddPage(grc_wxgui.Panel(self.Main), "Wideband Spectrum")
|
|
self.Main.AddPage(grc_wxgui.Panel(self.Main), "Channel Spectrum")
|
|
self.Main.AddPage(grc_wxgui.Panel(self.Main), "Soft Bits")
|
|
|
|
def set_ifreq(ifreq):
|
|
self.ifreq = ifreq
|
|
self._ifreq_text_box.set_value(self.ifreq)
|
|
self.src.set_center_freq(self.ifreq)
|
|
|
|
self._ifreq_text_box = forms.text_box(
|
|
parent=self.GetWin(),
|
|
value=self.ifreq,
|
|
callback=set_ifreq,
|
|
label="Center Frequency",
|
|
converter=forms.float_converter(),
|
|
)
|
|
self.Add(self._ifreq_text_box)
|
|
|
|
def set_iagc(iagc):
|
|
self.iagc = iagc
|
|
self._agc_check_box.set_value(self.iagc)
|
|
self.src.set_gain_mode(self.iagc, 0)
|
|
self.src.set_gain(0 if self.iagc == 1 else self.rfgain, 0)
|
|
|
|
self._agc_check_box = forms.check_box(
|
|
parent=self.GetWin(),
|
|
value=self.iagc,
|
|
callback=set_iagc,
|
|
label="Automatic Gain",
|
|
true=1,
|
|
false=0,
|
|
)
|
|
|
|
self.Add(self._agc_check_box)
|
|
|
|
def set_rfgain(rfgain):
|
|
self.rfgain = rfgain
|
|
self._rfgain_slider.set_value(self.rfgain)
|
|
self._rfgain_text_box.set_value(self.rfgain)
|
|
self.src.set_gain(0 if self.iagc == 1 else self.rfgain, 0)
|
|
|
|
_rfgain_sizer = wx.BoxSizer(wx.VERTICAL)
|
|
self._rfgain_text_box = forms.text_box(
|
|
parent=self.GetWin(),
|
|
sizer=_rfgain_sizer,
|
|
value=self.rfgain,
|
|
callback=set_rfgain,
|
|
label="RF Gain",
|
|
converter=forms.float_converter(),
|
|
proportion=0,
|
|
)
|
|
self._rfgain_slider = forms.slider(
|
|
parent=self.GetWin(),
|
|
sizer=_rfgain_sizer,
|
|
value=self.rfgain,
|
|
callback=set_rfgain,
|
|
minimum=0,
|
|
maximum=50,
|
|
num_steps=200,
|
|
style=wx.SL_HORIZONTAL,
|
|
cast=float,
|
|
proportion=1,
|
|
)
|
|
|
|
self.Add(_rfgain_sizer)
|
|
|
|
self.Add(self.Main)
|
|
|
|
def fftsink2_callback(x, y):
|
|
if abs(x / (sample_rate / 2)) > 0.9:
|
|
set_ifreq(self.ifreq + x / 2)
|
|
else:
|
|
sys.stderr.write("coarse tuned to: %d Hz\n" % x)
|
|
self.offset = x
|
|
self.tuner.set_center_freq(self.offset)
|
|
|
|
self.scope = fftsink2.fft_sink_c(self.Main.GetPage(0).GetWin(),
|
|
title="Wideband Spectrum (click to coarse tune)",
|
|
fft_size=1024,
|
|
sample_rate=sample_rate,
|
|
ref_scale=2.0,
|
|
ref_level=0,
|
|
y_divs=10,
|
|
fft_rate=10,
|
|
average=False,
|
|
avg_alpha=0.6)
|
|
|
|
self.Main.GetPage(0).Add(self.scope.win)
|
|
self.scope.set_callback(fftsink2_callback)
|
|
|
|
self.connect(self.src, self.scope)
|
|
|
|
def fftsink2_callback2(x, y):
|
|
self.offset = self.offset - (x / 10)
|
|
sys.stderr.write("fine tuned to: %d Hz\n" % self.offset)
|
|
self.tuner.set_center_freq(self.offset)
|
|
|
|
self.scope2 = fftsink2.fft_sink_c(self.Main.GetPage(1).GetWin(),
|
|
title="Channel Spectrum (click to fine tune)",
|
|
fft_size=1024,
|
|
sample_rate=out_sample_rate,
|
|
ref_scale=2.0,
|
|
ref_level=-20,
|
|
y_divs=10,
|
|
fft_rate=10,
|
|
average=False,
|
|
avg_alpha=0.6)
|
|
|
|
self.Main.GetPage(1).Add(self.scope2.win)
|
|
self.scope2.set_callback(fftsink2_callback2)
|
|
|
|
self.connect(self.resamp, self.scope2)
|
|
|
|
self.scope3 = scopesink2.scope_sink_f(
|
|
self.Main.GetPage(2).GetWin(),
|
|
title="Soft Bits",
|
|
sample_rate=out_sample_rate,
|
|
v_scale=0,
|
|
v_offset=0,
|
|
t_scale=0.001,
|
|
ac_couple=False,
|
|
xy_mode=False,
|
|
num_inputs=1,
|
|
trig_mode=TRIG_MODE_AUTO,
|
|
y_axis_label="Counts",
|
|
)
|
|
self.Main.GetPage(2).Add(self.scope3.win)
|
|
|
|
self.connect(self.demod, self.scope3)
|
|
|
|
def get_options():
|
|
parser = OptionParser(option_class=eng_option)
|
|
|
|
parser.add_option("-a", "--args", type="string", default="",
|
|
help="gr-osmosdr device arguments")
|
|
parser.add_option("-s", "--sample-rate", type="eng_float", default=1800000,
|
|
help="set receiver sample rate (default 1800000)")
|
|
parser.add_option("-f", "--frequency", type="eng_float", default=394.4e6,
|
|
help="set receiver center frequency")
|
|
parser.add_option("-g", "--gain", type="eng_float", default=None,
|
|
help="set receiver gain")
|
|
|
|
# demodulator related settings
|
|
parser.add_option("-l", "--log", action="store_true", default=False, help="dump debug .dat files")
|
|
parser.add_option("-L", "--low-pass", type="eng_float", default=25e3, help="low pass cut-off", metavar="Hz")
|
|
parser.add_option("-o", "--output-file", type="string", default="out.float", help="specify the bit output file")
|
|
parser.add_option("-v", "--verbose", action="store_true", default=False, help="dump demodulation data")
|
|
(options, args) = parser.parse_args()
|
|
if len(args) != 0:
|
|
parser.print_help()
|
|
raise SystemExit, 1
|
|
|
|
return (options)
|
|
|
|
if __name__ == '__main__':
|
|
tb = top_block()
|
|
tb.Run(True)
|