def __init__(self, center_frequency, sample_rate, decimation, filename, sample_format=None, threshold=7.0, signal_width=40e3, offline=False, max_queue_len=500, verbose=False):
gr.top_block.__init__(self, "Top Block")
self._center_frequency = center_frequency
self._signal_width = 40e3
self._input_sample_rate = sample_rate
self._verbose = verbose
self._threshold = threshold
self._filename = filename
self._offline = offline
self._max_queue_len = max_queue_len
self._fft_size = int(math.pow(2, 1 + int(math.log(self._input_sample_rate / 1000, 2)))) # fft is approx 1ms long
self._burst_pre_len = 2 * self._fft_size
self._burst_post_len = 8 * self._fft_size
self._burst_width= int(self._signal_width / (self._input_sample_rate / self._fft_size)) # Area to ignore around an already found signal in FFT bins
if decimation > 1:
self._use_pfb = True
# We will set up a filter bank with an odd number of outputs and
# and an over sampling ratio to still get the desired decimation.
# The goal is to still catch signal which (due to doppler shift) end up
# on the border of two channels.
# For this to work the desired decimation must be even.
if decimation % 2:
raise RuntimeError("The desired decimation must be 1 or an even number")
self._channels = decimation + 1
self._pfb_over_sample_ratio = self._channels / (self._channels - 1.)
pfb_output_sample_rate = int(round(float(self._input_sample_rate) / self._channels * self._pfb_over_sample_ratio))
assert pfb_output_sample_rate == self._input_sample_rate / decimation
# The over sampled region of the FIR filter contains half of the signal width and
# the transition region of the FIR filter.
# The bandwidth is simply increased by the signal width.
# A signal which has its center frequency directly on the border of
# two channels will reconstruct correclty on both channels.
self._fir_bw = (self._input_sample_rate / self._channels + self._signal_width) / 2
# The remaining bandwidth inside the over samples region is used to
# contain the transistion region of the filter.
# It can be multiplied by two as it is allowed to continue into the
# transition region of the neighboring channel.
# TODO: Draw a nice graphic how this works.
self._fir_tw = (pfb_output_sample_rate / 2 - self._fir_bw) * 2
# If the over sampling ratio is not large enough, there is not
# enough room to construct a transition region.
if self._fir_tw < 0:
raise RuntimeError("PFB over sampling ratio not enough to create a working FIR filter")
self._pfb_fir_filter = gnuradio.filter.firdes.low_pass_2(1, self._input_sample_rate, self._fir_bw, self._fir_tw, 60)
# If the transition width approaches 0, the filter size goes up significantly.
if len(self._pfb_fir_filter) > 200:
print >> sys.stderr, "Warning: The PFB FIR filter has an abnormal large number of taps:", len(self._pfb_fir_filter)
print >> sys.stderr, "Consider reducing the decimation factor or increase the over sampling ratio"
self._burst_sample_rate = pfb_output_sample_rate
if self._verbose:
print >> sys.stderr, "self._channels", self._channels
print >> sys.stderr, "len(self._pfb_fir_filter)", len(self._pfb_fir_filter)
print >> sys.stderr, "self._pfb_over_sample_ratio", self._pfb_over_sample_ratio
print >> sys.stderr, "self._fir_bw", self._fir_bw
print >> sys.stderr, "self._fir_tw", self._fir_tw
print >> sys.stderr, "self._burst_sample_rate", self._burst_sample_rate
else:
self._use_pfb = False
self._burst_sample_rate = self._input_sample_rate
# After 90 ms there needs to be a pause in the frame sturcture.
# Let's make that the limit for a detected burst
self._max_burst_len = int(self._burst_sample_rate * 0.09)
if self._verbose:
print >> sys.stderr, "require %.1f dB" % self._threshold
print >> sys.stderr, "burst_width: %d (= %.1f Hz)" % (self._burst_width, self._burst_width*self._input_sample_rate/self._fft_size)
if self._filename.endswith(".conf"):
import ConfigParser
config = ConfigParser.ConfigParser()
config.read(self._filename)
items = config.items("osmosdr-source")
d = {key: value for key, value in items}
if 'device_args' in d:
source = osmosdr.source(args=d['device_args'])
else:
source = osmosdr.source()
source.set_sample_rate(self._input_sample_rate)
source.set_center_freq(self._center_frequency, 0)
if 'gain' in d:
gain = int(d['gain'])
source.set_gain(gain, 0)
print >> sys.stderr, "(RF) Gain:", source.get_gain(0), '(Requested %d)' % gain
if 'if_gain' in d:
if_gain = int(d['if_gain'])
source.set_if_gain(if_gain, 0)
print >> sys.stderr, "IF Gain:", source.get_gain("IF", 0), '(Requested %d)' % if_gain
if 'mix_gain' in d:
mix_gain = int(d['mix_gain'])
source.set_mix_gain(mix_gain, 0)
print >> sys.stderr, "MIX Gain:", source.get_gain("MIX", 0), '(Requested %d)' % mix_gain
if 'bb_gain' in d:
bb_gain = int(d['bb_gain'])
source.set_bb_gain(bb_gain, 0)
print >> sys.stderr, "BB Gain:", source.get_gain("BB", 0), '(Requested %d)' % bb_gain
if 'bandwidth' in d:
bandwidth = int(d['bandwidth'])
source.set_bandwidth(bandwidth, 0)
print >> sys.stderr, "Bandwidth:", source.get_bandwidth(0), '(Requested %d)' % bandwidth
else:
source.set_bandwidth(0, 0)
print >> sys.stderr, "Warning: Setting bandwidth to", source.get_bandwidth(0)
#source.set_freq_corr($corr0, 0)
#source.set_dc_offset_mode($dc_offset_mode0, 0)
#source.set_iq_balance_mode($iq_balance_mode0, 0)
#source.set_gain_mode($gain_mode0, 0)
#source.set_antenna($ant0, 0)
converter = None
else:
if sample_format == "rtl":
converter = iridium.iuchar_to_complex()
itemsize = gr.sizeof_char
elif sample_format == "hackrf":
converter = blocks.interleaved_char_to_complex()
itemsize = gr.sizeof_char
elif sample_format == "sc16":
converter = blocks.interleaved_short_to_complex()
itemsize = gr.sizeof_short
elif sample_format == "float":
converter = None
itemsize = gr.sizeof_gr_complex
else:
raise RuntimeError("Unknown sample format for offline mode given")
source = blocks.file_source(itemsize=itemsize, filename=self._filename, repeat=False)
# Just to keep the code below a bit more portable
tb = self
#fft_burst_tagger::make(float center_frequency, int fft_size, int sample_rate,
# int burst_pre_len, int burst_post_len, int burst_width,
# int max_bursts, float threshold, int history_size, bool debug)
self._fft_burst_tagger = iridium.fft_burst_tagger(center_frequency=self._center_frequency,
fft_size=self._fft_size,
sample_rate=self._input_sample_rate,
burst_pre_len=self._burst_pre_len, burst_post_len=self._burst_post_len,
burst_width=self._burst_width,
max_bursts=100,
threshold=self._threshold,
history_size=512,
debug=self._verbose)
# Initial filter to filter the detected bursts. Runs at burst_sample_rate. Used to decimate the signal.
# TODO: Should probably be set to self._signal_width
input_filter = gnuradio.filter.firdes.low_pass_2(1, self._burst_sample_rate, 40e3/2, 40e3, 40)
#input_filter = gnuradio.filter.firdes.low_pass_2(1, self._burst_sample_rate, 42e3/2, 24e3, 40)
#print len(input_filter)
# Filter to find the start of the signal. Should be fairly narrow.
# TODO: 250000 appears as magic number here
start_finder_filter = gnuradio.filter.firdes.low_pass_2(1, 250000, 5e3/2, 10e3/2, 60)
#print len(start_finder_filter)
self._iridium_qpsk_demod = iridium.iridium_qpsk_demod_cpp()
#self._iridium_qpsk_demod = iridium.iridium_qpsk_demod(250000)
if self._use_pfb:
self._burst_to_pdu_converters = []
self._burst_downmixers = []
sinks = []
for channel in range(self._channels):
center = channel if channel <= self._channels / 2 else (channel - self._channels)
# Second and third parameters tell the block where after the PFB it sits.
relative_center = center / float(self._channels)
relative_span = 1. / self._channels
relative_sample_rate = relative_span * self._pfb_over_sample_ratio
burst_to_pdu_converter = iridium.tagged_burst_to_pdu(self._max_burst_len, relative_center,
relative_span, relative_sample_rate, self._max_queue_len, not self._offline)
burst_downmixer = iridium.burst_downmix(self._burst_sample_rate,
int(0.007 * 250000), 0, (input_filter), (start_finder_filter))
self._burst_downmixers.append(burst_downmixer)
self._burst_to_pdu_converters.append(burst_to_pdu_converter)
#pfb_debug_sinks = [blocks.file_sink(itemsize=gr.sizeof_gr_complex, filename="/tmp/channel-%d.f32"%i) for i in range(self._channels)]
pfb_debug_sinks = None
pfb = gnuradio.filter.pfb.channelizer_ccf(numchans=self._channels, taps=self._pfb_fir_filter, oversample_rate=self._pfb_over_sample_ratio)
if converter:
tb.connect(source, converter, self._fft_burst_tagger, pfb)
else:
tb.connect(source, self._fft_burst_tagger, pfb)
for i in range(self._channels):
tb.connect((pfb, i), self._burst_to_pdu_converters[i])
if pfb_debug_sinks:
tb.connect((pfb, i), pfb_debug_sinks[i])
tb.msg_connect((self._burst_to_pdu_converters[i], 'cpdus'), (self._burst_downmixers[i], 'cpdus'))
tb.msg_connect((self._burst_downmixers[i], 'burst_handled'), (self._burst_to_pdu_converters[i], 'burst_handled'))
tb.msg_connect((self._burst_downmixers[i], 'cpdus'), (self._iridium_qpsk_demod, 'cpdus'))
else:
burst_downmix = iridium.burst_downmix(self._burst_sample_rate, int(0.007 * 250000), 0, (input_filter), (start_finder_filter))
burst_to_pdu = iridium.tagged_burst_to_pdu(self._max_burst_len, 0.0, 1.0, 1.0, self._max_queue_len, not self._offline)
if converter:
#multi = blocks.multiply_const_cc(1/128.)
#tb.connect(source, converter, multi, self._fft_burst_tagger, burst_to_pdu)
tb.connect(source, converter, self._fft_burst_tagger, burst_to_pdu)
else:
tb.connect(source, self._fft_burst_tagger, burst_to_pdu)
tb.msg_connect((burst_to_pdu, 'cpdus'), (burst_downmix, 'cpdus'))
tb.msg_connect((burst_downmix, 'burst_handled'), (burst_to_pdu, 'burst_handled'))
# Final connection to the demodulator. It prints the output to stdout
tb.msg_connect((burst_downmix, 'cpdus'), (self._iridium_qpsk_demod, 'cpdus'))
self._burst_downmixers = [burst_downmix]
self._burst_to_pdu_converters = [burst_to_pdu]
def __init__(self,
center_frequency,
sample_rate,
decimation,
filename,
sample_format=None,
threshold=7.0,
signal_width=40e3,
offline=False,
max_queue_len=500,
handle_multiple_frames_per_burst=False,
raw_capture_filename=None,
max_bursts=0,
verbose=False):
gr.top_block.__init__(self, "Top Block")
self._center_frequency = center_frequency
self._burst_width = 40e3
self._input_sample_rate = sample_rate
self._verbose = verbose
self._threshold = threshold
self._filename = filename
self._offline = offline
self._max_queue_len = max_queue_len
self._handle_multiple_frames_per_burst = handle_multiple_frames_per_burst
self._fft_size = int(
math.pow(2, 1 + int(math.log(self._input_sample_rate / 1000,
2)))) # fft is approx 1ms long
self._burst_pre_len = 2 * self._fft_size
self._burst_post_len = 8 * self._fft_size
# Just to keep the code below a bit more portable
tb = self
if decimation > 1:
self._use_pfb = True
# We will set up a filter bank with an odd number of outputs and
# and an over sampling ratio to still get the desired decimation.
# The goal is to still catch signal which (due to doppler shift) end up
# on the border of two channels.
# For this to work the desired decimation must be even.
if decimation % 2:
raise RuntimeError(
"The desired decimation must be 1 or an even number")
self._channels = decimation + 1
self._pfb_over_sample_ratio = self._channels / (self._channels -
1.)
pfb_output_sample_rate = int(
round(
float(self._input_sample_rate) / self._channels *
self._pfb_over_sample_ratio))
assert pfb_output_sample_rate == self._input_sample_rate / decimation
# The over sampled region of the FIR filter contains half of the signal width and
# the transition region of the FIR filter.
# The bandwidth is simply increased by the signal width.
# A signal which has its center frequency directly on the border of
# two channels will reconstruct correclty on both channels.
self._fir_bw = (self._input_sample_rate / self._channels +
self._burst_width) / 2
# The remaining bandwidth inside the over samples region is used to
# contain the transistion region of the filter.
# It can be multiplied by two as it is allowed to continue into the
# transition region of the neighboring channel.
# TODO: Draw a nice graphic how this works.
self._fir_tw = (pfb_output_sample_rate / 2 - self._fir_bw) * 2
# If the over sampling ratio is not large enough, there is not
# enough room to construct a transition region.
if self._fir_tw < 0:
raise RuntimeError(
"PFB over sampling ratio not enough to create a working FIR filter"
)
self._pfb_fir_filter = gnuradio.filter.firdes.low_pass_2(
1, self._input_sample_rate, self._fir_bw, self._fir_tw, 60)
# If the transition width approaches 0, the filter size goes up significantly.
if len(self._pfb_fir_filter) > 200:
print(
"Warning: The PFB FIR filter has an abnormal large number of taps:",
len(self._pfb_fir_filter),
file=sys.stderr)
print(
"Consider reducing the decimation factor or increase the over sampling ratio",
file=sys.stderr)
self._burst_sample_rate = pfb_output_sample_rate
if self._verbose:
print("self._channels", self._channels, file=sys.stderr)
print("len(self._pfb_fir_filter)",
len(self._pfb_fir_filter),
file=sys.stderr)
print("self._pfb_over_sample_ratio",
self._pfb_over_sample_ratio,
file=sys.stderr)
print("self._fir_bw", self._fir_bw, file=sys.stderr)
print("self._fir_tw", self._fir_tw, file=sys.stderr)
print("self._burst_sample_rate",
self._burst_sample_rate,
file=sys.stderr)
else:
self._use_pfb = False
self._burst_sample_rate = self._input_sample_rate
# After 90 ms there needs to be a pause in the frame sturcture.
# Let's make that the limit for a detected burst
self._max_burst_len = int(self._burst_sample_rate * 0.09)
if self._verbose:
print("require %.1f dB" % self._threshold, file=sys.stderr)
print("burst_width: %d Hz" % self._burst_width, file=sys.stderr)
if self._filename.endswith(".conf"):
import configparser
config = configparser.ConfigParser()
config.read(self._filename)
items = config.items("osmosdr-source")
d = {key: value for key, value in items}
import osmosdr
if 'device_args' in d:
source = osmosdr.source(args=d['device_args'])
else:
source = osmosdr.source()
source.set_sample_rate(self._input_sample_rate)
source.set_center_freq(self._center_frequency, 0)
if 'gain' in d:
gain = int(d['gain'])
source.set_gain(gain, 0)
print("(RF) Gain:",
source.get_gain(0),
'(Requested %d)' % gain,
file=sys.stderr)
for key, value in d.items():
if key.endswith("_gain"):
gain_option_name = key.split('_')[0]
gain_value = int(value)
def match_gain(gain, gain_names):
for gain_name in gain_names:
if gain.lower() == gain_name.lower():
return gain_name
return None
gain_name = match_gain(gain_option_name,
source.get_gain_names())
if gain_name is not None:
source.set_gain(gain_value, gain_name, 0)
print(gain_name,
"Gain:",
source.get_gain(gain_name, 0),
'(Requested %d)' % gain_value,
file=sys.stderr)
else:
print("WARNING: Gain",
gain_option_name,
"not supported by source!",
file=sys.stderr)
print("Supported gains:",
source.get_gain_names(),
file=sys.stderr)
if 'bandwidth' in d:
bandwidth = int(d['bandwidth'])
source.set_bandwidth(bandwidth, 0)
print("Bandwidth:",
source.get_bandwidth(0),
'(Requested %d)' % bandwidth,
file=sys.stderr)
else:
source.set_bandwidth(0, 0)
print("Warning: Setting bandwidth to",
source.get_bandwidth(0),
file=sys.stderr)
if 'antenna' in d:
antenna = d['antenna']
source.set_antenna(antenna, 0)
print("Antenna:",
source.get_antenna(0),
'(Requested %s)' % antenna,
file=sys.stderr)
else:
print("Warning: Setting antenna to",
source.get_antenna(0),
file=sys.stderr)
#source.set_freq_corr($corr0, 0)
#source.set_dc_offset_mode($dc_offset_mode0, 0)
#source.set_iq_balance_mode($iq_balance_mode0, 0)
#source.set_gain_mode($gain_mode0, 0)
#source.set_antenna($ant0, 0)
else:
if sample_format == "rtl":
converter = iridium.iuchar_to_complex()
itemsize = gr.sizeof_char
elif sample_format == "hackrf":
converter = blocks.interleaved_char_to_complex()
itemsize = gr.sizeof_char
elif sample_format == "sc16":
converter = blocks.interleaved_short_to_complex()
itemsize = gr.sizeof_short
elif sample_format == "float":
converter = None
itemsize = gr.sizeof_gr_complex
else:
raise RuntimeError(
"Unknown sample format for offline mode given")
file_source = blocks.file_source(itemsize=itemsize,
filename=self._filename,
repeat=False)
if converter:
#multi = blocks.multiply_const_cc(1/128.)
#tb.connect(file_source, converter, multi)
#source = multi
tb.connect(file_source, converter)
source = converter
else:
source = file_source
#fft_burst_tagger::make(float center_frequency, int fft_size, int sample_rate,
# int burst_pre_len, int burst_post_len, int burst_width,
# int max_bursts, float threshold, int history_size, bool debug)
self._fft_burst_tagger = iridium.fft_burst_tagger(
center_frequency=self._center_frequency,
fft_size=self._fft_size,
sample_rate=self._input_sample_rate,
burst_pre_len=self._burst_pre_len,
burst_post_len=self._burst_post_len,
burst_width=int(self._burst_width),
max_bursts=max_bursts,
threshold=self._threshold,
history_size=512,
debug=self._verbose)
# Initial filter to filter the detected bursts. Runs at burst_sample_rate. Used to decimate the signal.
# TODO: Should probably be set to self._burst_width
input_filter = gnuradio.filter.firdes.low_pass_2(
1, self._burst_sample_rate, 40e3 / 2, 40e3, 40)
#input_filter = gnuradio.filter.firdes.low_pass_2(1, self._burst_sample_rate, 42e3/2, 24e3, 40)
#print len(input_filter)
# Filter to find the start of the signal. Should be fairly narrow.
# TODO: 250000 appears as magic number here
start_finder_filter = gnuradio.filter.firdes.low_pass_2(
1, 250000, 5e3 / 2, 10e3 / 2, 60)
#print len(start_finder_filter)
self._iridium_qpsk_demod = iridium.iridium_qpsk_demod_cpp()
self._frame_sorter = iridium.frame_sorter()
self._iridium_frame_printer = iridium.iridium_frame_printer()
#self._iridium_qpsk_demod = iridium.iridium_qpsk_demod(250000)
if raw_capture_filename:
raw_sink = blocks.file_sink(itemsize=gr.sizeof_gr_complex,
filename=raw_capture_filename)
tb.connect(source, raw_sink)
# Enable the following if not fast enough
#self._burst_to_pdu_converters = []
#self._burst_downmixers = []
#return
tb.connect(source, self._fft_burst_tagger)
if self._use_pfb:
self._burst_to_pdu_converters = []
self._burst_downmixers = []
sinks = []
for channel in range(self._channels):
center = channel if channel <= self._channels / 2 else (
channel - self._channels)
# Second and third parameters tell the block where after the PFB it sits.
relative_center = center / float(self._channels)
relative_span = 1. / self._channels
relative_sample_rate = relative_span * self._pfb_over_sample_ratio
burst_to_pdu_converter = iridium.tagged_burst_to_pdu(
self._max_burst_len, relative_center, relative_span,
relative_sample_rate, self._max_queue_len,
not self._offline)
burst_downmixer = iridium.burst_downmix(
self._burst_sample_rate, int(0.007 * 250000), 0,
(input_filter), (start_finder_filter),
self._handle_multiple_frames_per_burst)
self._burst_downmixers.append(burst_downmixer)
self._burst_to_pdu_converters.append(burst_to_pdu_converter)
#pfb_debug_sinks = [blocks.file_sink(itemsize=gr.sizeof_gr_complex, filename="/tmp/channel-%d.f32"%i) for i in range(self._channels)]
pfb_debug_sinks = None
pfb = gnuradio.filter.pfb.channelizer_ccf(
numchans=self._channels,
taps=self._pfb_fir_filter,
oversample_rate=self._pfb_over_sample_ratio)
tb.connect(self._fft_burst_tagger, pfb)
for i in range(self._channels):
tb.connect((pfb, i), self._burst_to_pdu_converters[i])
if pfb_debug_sinks:
tb.connect((pfb, i), pfb_debug_sinks[i])
tb.msg_connect((self._burst_to_pdu_converters[i], 'cpdus'),
(self._burst_downmixers[i], 'cpdus'))
tb.msg_connect(
(self._burst_downmixers[i], 'burst_handled'),
(self._burst_to_pdu_converters[i], 'burst_handled'))
tb.msg_connect((self._burst_downmixers[i], 'cpdus'),
(self._iridium_qpsk_demod, 'cpdus'))
else:
burst_downmix = iridium.burst_downmix(
self._burst_sample_rate, int(0.007 * 250000), 0,
(input_filter), (start_finder_filter),
self._handle_multiple_frames_per_burst)
burst_to_pdu = iridium.tagged_burst_to_pdu(self._max_burst_len,
0.0, 1.0, 1.0,
self._max_queue_len,
not self._offline)
tb.connect(self._fft_burst_tagger, burst_to_pdu)
tb.msg_connect((burst_to_pdu, 'cpdus'), (burst_downmix, 'cpdus'))
tb.msg_connect((burst_downmix, 'burst_handled'),
(burst_to_pdu, 'burst_handled'))
# Final connection to the demodulator. It prints the output to stdout
tb.msg_connect((burst_downmix, 'cpdus'),
(self._iridium_qpsk_demod, 'cpdus'))
self._burst_downmixers = [burst_downmix]
self._burst_to_pdu_converters = [burst_to_pdu]
tb.msg_connect((self._iridium_qpsk_demod, 'pdus'),
(self._frame_sorter, 'pdus'))
tb.msg_connect((self._frame_sorter, 'pdus'),
(self._iridium_frame_printer, 'pdus'))
def __init__(self,
center_frequency,
sample_rate,
decimation,
filename,
sample_format=None,
threshold=7.0,
burst_width=40e3,
offline=False,
max_queue_len=500,
handle_multiple_frames_per_burst=False,
raw_capture_filename=None,
debug_id=None,
max_bursts=0,
verbose=False,
file_info=None,
samples_per_symbol=10,
config={}):
gr.top_block.__init__(self, "Top Block")
self.handle_sigint = False
self._center_frequency = center_frequency
self._burst_width = burst_width
self._input_sample_rate = sample_rate
self._verbose = verbose
self._threshold = threshold
self._filename = filename
self._offline = offline
self._max_queue_len = max_queue_len
self._handle_multiple_frames_per_burst = handle_multiple_frames_per_burst
# Sample rate of the bursts exiting the burst downmix block
self._burst_sample_rate = 25000 * samples_per_symbol
assert (self._input_sample_rate /
decimation) % self._burst_sample_rate == 0
self._fft_size = 2**round(math.log(self._input_sample_rate / 1000,
2)) # FFT is approx. 1 ms long
self._burst_pre_len = 2 * self._fft_size
# Keep 16 ms of signal after the FFT loses track
self._burst_post_len = int(self._input_sample_rate * 16e-3)
# Just to keep the code below a bit more portable
tb = self
if decimation > 1:
self._use_pfb = True
# We will set up a filter bank with an odd number of outputs and
# and an over sampling ratio to still get the desired decimation.
# The goal is to reconstruct signals which (due to Doppler shift) end up
# on the border of two channels.
# For this to work the desired decimation must be even.
if decimation % 2:
raise RuntimeError(
"The desired decimation must be 1 or an even number")
self._channels = decimation + 1
self._pfb_over_sample_ratio = self._channels / (self._channels -
1.)
pfb_output_sample_rate = int(
round(
float(self._input_sample_rate) / self._channels *
self._pfb_over_sample_ratio))
assert pfb_output_sample_rate == self._input_sample_rate / decimation
assert pfb_output_sample_rate % self._burst_sample_rate == 0
# The over sampled region of the FIR filter contains half of the signal width and
# the transition region of the FIR filter.
# The bandwidth is simply increased by the signal width.
# A signal which has its center frequency directly on the border of
# two channels will reconstruct correctly on both channels.
self._fir_bw = (self._input_sample_rate / self._channels +
self._burst_width) / 2
# The remaining bandwidth inside the over sampled region is used to
# contain the transition region of the filter.
# It can be multiplied by two as it is allowed to continue into the
# transition region of the neighboring channel.
# Some details can be found here: https://youtu.be/6ngYp8W-AX0?t=2289
self._fir_tw = (pfb_output_sample_rate / 2 - self._fir_bw) * 2
# Real world data shows only a minor degradation in performance when
# doubling the transition width.
self._fir_tw *= 2
# If the over sampling ratio is not large enough, there is not
# enough room to construct a transition region.
if self._fir_tw < 0:
raise RuntimeError(
"PFB over sampling ratio not enough to create a working FIR filter"
)
self._pfb_fir_filter = gnuradio.filter.firdes.low_pass_2(
1, self._input_sample_rate, self._fir_bw, self._fir_tw, 60)
# If the transition width approaches 0, the filter size goes up significantly.
if len(self._pfb_fir_filter) > 300:
print(
"Warning: The PFB FIR filter has an abnormal large number of taps:",
len(self._pfb_fir_filter),
file=sys.stderr)
print("Consider reducing the decimation factor",
file=sys.stderr)
pfb_input_delay = (
len(self._pfb_fir_filter) +
1) // 2 - self._channels / self._pfb_over_sample_ratio
self._pfb_delay = pfb_input_delay / decimation
self._channel_sample_rate = pfb_output_sample_rate
if self._verbose:
print("self._channels", self._channels, file=sys.stderr)
print("len(self._pfb_fir_filter)",
len(self._pfb_fir_filter),
file=sys.stderr)
print("self._pfb_over_sample_ratio",
self._pfb_over_sample_ratio,
file=sys.stderr)
print("self._fir_bw", self._fir_bw, file=sys.stderr)
print("self._fir_tw", self._fir_tw, file=sys.stderr)
print("self._channel_sample_rate",
self._channel_sample_rate,
file=sys.stderr)
else:
self._use_pfb = False
self._channel_sample_rate = self._input_sample_rate
self._channels = 1
# After 90 ms there needs to be a pause in the frame sturcture.
# Let's make that the limit for a detected burst
self._max_burst_len = int(self._channel_sample_rate * 0.09)
if self._verbose:
print("require %.1f dB" % self._threshold, file=sys.stderr)
print("burst_width: %d Hz" % self._burst_width, file=sys.stderr)
if config['source'] == 'osmosdr':
d = config["osmosdr-source"]
# work around https://github.com/gnuradio/gnuradio/issues/5121
sys.path.append('/usr/local/lib/python3/dist-packages')
import osmosdr
if 'device_args' in d:
source = osmosdr.source(args=d['device_args'])
else:
source = osmosdr.source()
source.set_time_now(osmosdr.time_spec_t.get_system_time())
source.set_sample_rate(self._input_sample_rate)
source.set_center_freq(self._center_frequency, 0)
if 'gain' in d:
gain = int(d['gain'])
source.set_gain(gain, 0)
print("(RF) Gain:",
source.get_gain(0),
'(Requested %d)' % gain,
file=sys.stderr)
for key, value in d.items():
if key.endswith("_gain"):
gain_option_name = key.split('_')[0]
gain_value = int(value)
def match_gain(gain, gain_names):
for gain_name in gain_names:
if gain.lower() == gain_name.lower():
return gain_name
return None
gain_name = match_gain(gain_option_name,
source.get_gain_names())
if gain_name is not None:
source.set_gain(gain_value, gain_name, 0)
print(gain_name,
"Gain:",
source.get_gain(gain_name, 0),
'(Requested %d)' % gain_value,
file=sys.stderr)
else:
print("WARNING: Gain",
gain_option_name,
"not supported by source!",
file=sys.stderr)
print("Supported gains:",
source.get_gain_names(),
file=sys.stderr)
if 'bandwidth' in d:
bandwidth = int(d['bandwidth'])
source.set_bandwidth(bandwidth, 0)
print("Bandwidth:",
source.get_bandwidth(0),
'(Requested %d)' % bandwidth,
file=sys.stderr)
else:
source.set_bandwidth(0, 0)
print("Warning: Setting bandwidth to",
source.get_bandwidth(0),
file=sys.stderr)
if 'antenna' in d:
antenna = d['antenna']
source.set_antenna(antenna, 0)
print("Antenna:",
source.get_antenna(0),
'(Requested %s)' % antenna,
file=sys.stderr)
else:
print("Warning: Setting antenna to",
source.get_antenna(0),
file=sys.stderr)
#source.set_freq_corr($corr0, 0)
#source.set_dc_offset_mode($dc_offset_mode0, 0)
#source.set_iq_balance_mode($iq_balance_mode0, 0)
#source.set_gain_mode($gain_mode0, 0)
#source.set_antenna($ant0, 0)
else:
if sample_format == "cu8":
converter = iridium.iuchar_to_complex()
itemsize = gr.sizeof_char
scale = 1
itemtype = np.uint8
elif sample_format == "ci8":
converter = blocks.interleaved_char_to_complex()
itemsize = gr.sizeof_char
scale = 1 / 128.
itemtype = np.int8
elif sample_format == "ci16_le":
converter = blocks.interleaved_short_to_complex()
itemsize = gr.sizeof_short
scale = 1 / 32768.
itemtype = np.int16
elif sample_format == "cf32_le":
converter = None
itemsize = gr.sizeof_gr_complex
itemtype = np.complex64
else:
raise RuntimeError(
"Unknown sample format for offline mode given")
if config['source'] == 'stdin':
file_source = blocks.file_descriptor_source(itemsize=itemsize,
fd=0,
repeat=False)
elif config['source'] == 'object':
from iridium.file_object_source import file_object_source
file_source = file_object_source(fileobject=config['object'],
itemtype=itemtype)
else:
file_source = blocks.file_source(itemsize=itemsize,
filename=config['file'],
repeat=False)
self.source = file_source # XXX: keep reference
if converter:
multi = blocks.multiply_const_cc(scale)
tb.connect(file_source, converter, multi)
source = multi
else:
source = file_source
self._fft_burst_tagger = iridium.fft_burst_tagger(
center_frequency=self._center_frequency,
fft_size=self._fft_size,
sample_rate=self._input_sample_rate,
burst_pre_len=self._burst_pre_len,
burst_post_len=self._burst_post_len,
burst_width=int(self._burst_width),
max_bursts=max_bursts,
threshold=self._threshold,
history_size=512,
offline=self._offline,
debug=self._verbose)
# Initial filter to filter the detected bursts. Runs at burst_sample_rate. Used to decimate the signal.
input_filter = gnuradio.filter.firdes.low_pass_2(
1, self._channel_sample_rate, self._burst_width / 2,
self._burst_width, 40)
#input_filter = gnuradio.filter.firdes.low_pass_2(1, self._channel_sample_rate, 42e3/2, 24e3, 40)
#print len(input_filter)
# Filter to find the start of the signal. Should be fairly narrow.
start_finder_filter = gnuradio.filter.firdes.low_pass_2(
1, self._burst_sample_rate, 5e3 / 2, 10e3 / 2, 60)
#print len(start_finder_filter)
self._iridium_qpsk_demod = iridium.iridium_qpsk_demod_cpp(
self._channels)
self._frame_sorter = iridium.frame_sorter()
self._iridium_frame_printer = iridium.iridium_frame_printer(file_info)
if raw_capture_filename:
multi = blocks.multiply_const_cc(32768)
converter = blocks.complex_to_interleaved_short()
raw_sink = blocks.file_sink(itemsize=gr.sizeof_short,
filename=raw_capture_filename)
tb.connect(source, multi, converter, raw_sink)
# Enable the following if not fast enough
#self._burst_to_pdu_converters = []
#self._burst_downmixers = []
#return
tb.connect(source, self._fft_burst_tagger)
if self._use_pfb:
self._burst_to_pdu_converters = []
self._burst_downmixers = []
sinks = []
for channel in range(self._channels):
center = channel if channel <= self._channels / 2 else (
channel - self._channels)
# Second and third parameters tell the block where after the PFB it sits.
relative_center = center / float(self._channels)
relative_span = 1. / self._channels
relative_sample_rate = relative_span * self._pfb_over_sample_ratio
burst_to_pdu_converter = iridium.tagged_burst_to_pdu(
self._max_burst_len, relative_center, relative_span,
relative_sample_rate, -self._pfb_delay,
self._max_queue_len, not self._offline)
burst_downmixer = iridium.burst_downmix(
self._burst_sample_rate,
int(0.007 * self._burst_sample_rate), 0, (input_filter),
(start_finder_filter),
self._handle_multiple_frames_per_burst)
if debug_id is not None: burst_downmixer.debug_id(debug_id)
self._burst_downmixers.append(burst_downmixer)
self._burst_to_pdu_converters.append(burst_to_pdu_converter)
#pfb_debug_sinks = [blocks.file_sink(itemsize=gr.sizeof_gr_complex, filename="/tmp/channel-%d.f32"%i) for i in range(self._channels)]
pfb_debug_sinks = None
pfb = gnuradio.filter.pfb.channelizer_ccf(
numchans=self._channels,
taps=self._pfb_fir_filter,
oversample_rate=self._pfb_over_sample_ratio)
tb.connect(self._fft_burst_tagger, pfb)
for i in range(self._channels):
tb.connect((pfb, i), self._burst_to_pdu_converters[i])
if pfb_debug_sinks:
tb.connect((pfb, i), pfb_debug_sinks[i])
tb.msg_connect((self._burst_to_pdu_converters[i], 'cpdus'),
(self._burst_downmixers[i], 'cpdus'))
tb.msg_connect(
(self._burst_downmixers[i], 'burst_handled'),
(self._burst_to_pdu_converters[i], 'burst_handled'))
tb.msg_connect((self._burst_downmixers[i], 'cpdus'),
(self._iridium_qpsk_demod, 'cpdus%d' % i))
else:
burst_downmix = iridium.burst_downmix(
self._burst_sample_rate, int(0.007 * self._burst_sample_rate),
0, (input_filter), (start_finder_filter),
self._handle_multiple_frames_per_burst)
if debug_id is not None: burst_downmix.debug_id(debug_id)
burst_to_pdu = iridium.tagged_burst_to_pdu(self._max_burst_len,
0.0, 1.0, 1.0, 0,
self._max_queue_len,
not self._offline)
tb.connect(self._fft_burst_tagger, burst_to_pdu)
tb.msg_connect((burst_to_pdu, 'cpdus'), (burst_downmix, 'cpdus'))
tb.msg_connect((burst_downmix, 'burst_handled'),
(burst_to_pdu, 'burst_handled'))
# Final connection to the demodulator. It prints the output to stdout
tb.msg_connect((burst_downmix, 'cpdus'),
(self._iridium_qpsk_demod, 'cpdus'))
self._burst_downmixers = [burst_downmix]
self._burst_to_pdu_converters = [burst_to_pdu]
tb.msg_connect((self._iridium_qpsk_demod, 'pdus'),
(self._frame_sorter, 'pdus'))
tb.msg_connect((self._frame_sorter, 'pdus'),
(self._iridium_frame_printer, 'pdus'))
