#!/usr/bin/env python
# This module contains the functions used to demodulate raw RF files
# in I-Q format. These functions use the gnuradio libraries to tune
# to the signal, then filter and demodulate it.
#
# Each class below with the suffix "_flowgraph" contains all of the
# gnuradio blocks required to process the I-Q data to a digital baseband
# waveform. This baseband waveform is output to a file
from gnuradio import gr
from gnuradio import analog
from gnuradio import blocks
from gnuradio import digital
#from gnuradio import eng_notation
from gnuradio import filter
#from gnuradio.eng_option import eng_option
from gnuradio.filter import firdes
from math import pi
##############################################################
# This flowgraph consists of the following blocks:
# - a File Source that
# - a Frequency Translating FIR filter that tunes to the target signal
# - a Complex to Mag block that demodules the OOK signal
# - an Add Const block that shifts the demodulated signal downwards, centering
# it around zero on the y-axis
# - a Binary Slicer that converts centered signal from floating point to binary
# - a File Sink that outputs
class ook_flowgraph(gr.top_block):
def __init__(self, samp_rate_in, samp_rate_out, center_freq,
tune_freq, channel_width, transition_width, threshold,
iq_filename, dig_out_filename):
gr.top_block.__init__(self)
##################################################
# Variables
##################################################
self.cutoff_freq = channel_width/2
self.firdes_taps = firdes.low_pass(1, samp_rate_in,
self.cutoff_freq,
transition_width)
##################################################
# Blocks
##################################################
self.tuning_filter_0 = filter.freq_xlating_fir_filter_ccc(int(samp_rate_in/samp_rate_out),
(self.firdes_taps),
tune_freq-center_freq,
samp_rate_in)
self.digital_binary_slicer_fb_0 = digital.binary_slicer_fb()
self.blocks_file_source_0 = blocks.file_source(gr.sizeof_gr_complex*1, iq_filename, False)
self.blocks_complex_to_mag_0 = blocks.complex_to_mag(1)
self.blocks_add_const_vxx_0 = blocks.add_const_vff((-1*threshold, ))
# message sink is primary method of getting baseband data into waveconverter
self.sink_queue = gr.msg_queue()
self.blocks_message_sink_0 = blocks.message_sink(gr.sizeof_char*1, self.sink_queue, False)
# if directed, we also dump the baseband data into a file
if len(dig_out_filename) > 0:
print "Outputing baseband to waveform to " + dig_out_filename
self.blocks_file_sink_0 = blocks.file_sink(gr.sizeof_char*1, dig_out_filename, False)
self.blocks_file_sink_0.set_unbuffered(False)
##################################################
# Connections
##################################################
self.connect((self.blocks_add_const_vxx_0, 0), (self.digital_binary_slicer_fb_0, 0))
self.connect((self.blocks_complex_to_mag_0, 0), (self.blocks_add_const_vxx_0, 0))
self.connect((self.blocks_file_source_0, 0), (self.tuning_filter_0, 0))
self.connect((self.tuning_filter_0, 0), (self.blocks_complex_to_mag_0, 0))
self.connect((self.digital_binary_slicer_fb_0, 0), (self.blocks_message_sink_0, 0))
if len(dig_out_filename) > 0:
self.connect((self.digital_binary_slicer_fb_0, 0), (self.blocks_file_sink_0, 0))
##############################################################
# This flowgraph consists of the following blocks:
# - a File Source that
# - a Frequency Translating FIR filter that tunes to the target signal
# - a quadrature demod block that demodules the FSK signal
# - an Add Const block that shifts the demodulated signal downwards, centering
# it around zero on the y-axis
# - a Binary Slicer that converts centered signal from floating point to binary
# - a File Sink that outputs
class fsk_flowgraph(gr.top_block):
def __init__(self, samp_rate_in, samp_rate_out, center_freq,
tune_freq, channel_width, transition_width, threshold, fsk_deviation, fskSquelch,
iq_filename, dig_out_filename):
gr.top_block.__init__(self)
##################################################
# Variables
##################################################
self.cutoff_freq = channel_width/2
self.firdes_taps = firdes.low_pass(1, samp_rate_in,
self.cutoff_freq,
transition_width)
##################################################
# Blocks
##################################################
self.blocks_file_source_0 = blocks.file_source(gr.sizeof_gr_complex*1, iq_filename, False)
self.blocks_tuning_filter_0 = filter.freq_xlating_fir_filter_ccc(int(samp_rate_in/samp_rate_out),
(self.firdes_taps),
tune_freq-center_freq,
samp_rate_in)
self.analog_pwr_squelch_xx_0 = analog.pwr_squelch_cc(fskSquelch, 1, 1, False)
self.blocks_quadrature_demod_0 = analog.quadrature_demod_cf(samp_rate_out/(2*pi*fsk_deviation/2))
self.blocks_add_const_vxx_0 = blocks.add_const_vff((-1*threshold, ))
self.blocks_digital_binary_slicer_fb_0 = digital.binary_slicer_fb()
# swapped message sink for file sink
#self.blocks_file_sink_0 = blocks.file_sink(gr.sizeof_char*1, dig_out_filename, False)
#self.blocks_file_sink_0.set_unbuffered(False)
self.sink_queue = gr.msg_queue()
self.blocks_message_sink_0 = blocks.message_sink(gr.sizeof_char*1, self.sink_queue, False)
##################################################
# Connections
##################################################
self.connect((self.blocks_file_source_0, 0), (self.blocks_tuning_filter_0, 0))
self.connect((self.blocks_tuning_filter_0, 0), (self.analog_pwr_squelch_xx_0, 0))
self.connect((self.analog_pwr_squelch_xx_0, 0), (self.blocks_quadrature_demod_0, 0))
self.connect((self.blocks_quadrature_demod_0, 0), (self.blocks_add_const_vxx_0, 0))
self.connect((self.blocks_add_const_vxx_0, 0), (self.blocks_digital_binary_slicer_fb_0, 0))
#self.connect((self.digital_binary_slicer_fb_0, 0), (self.blocks_file_sink_0, 0))
self.connect((self.blocks_digital_binary_slicer_fb_0, 0), (self.blocks_message_sink_0, 0))
##############################################################
# This flowgraph consists of the following blocks:
# - a File Source that
# - a Frequency Translating FIR filter that tunes to the target signal
# - a quadrature demod block that demodules the FSK signal
# - an Add Const block that shifts the demodulated signal downwards, centering
# it around zero on the y-axis
# - a Binary Slicer that converts centered signal from floating point to binary
# - a File Sink that outputs
class fsk_hopping_flowgraph(gr.top_block):
def __init__(self, samp_rate_in, samp_rate_out, center_freq,
tune_freq0, tune_freq1, tune_freq2,
channel_width, transition_width, threshold, fsk_deviation, fskSquelch,
iq_filename, dig_out_filename):
gr.top_block.__init__(self)
##################################################
# Variables
##################################################
self.cutoff_freq = channel_width/2
self.firdes_taps = firdes.low_pass(1, samp_rate_in,
self.cutoff_freq,
transition_width)
self.nfilts = 32
self.symbol_rate = 16000
self.samples_per_symbol = int(samp_rate_out/self.symbol_rate)
self.rrc_taps = firdes.root_raised_cosine(self.nfilts, samp_rate_out, self.symbol_rate, 0.35, self.nfilts)
##################################################
# Blocks
##################################################
self.blocks_file_source_0 = blocks.file_source(gr.sizeof_gr_complex*1, iq_filename, False)
# flow for channel 0
self.blocks_tuning_filter_0 = filter.freq_xlating_fir_filter_ccc(int(samp_rate_in/samp_rate_out),
(self.firdes_taps),
tune_freq0-center_freq,
samp_rate_in)
self.analog_pwr_squelch_xx_0 = analog.pwr_squelch_cc(fskSquelch, 1, 1, False)
self.blocks_quadrature_demod_0 = analog.quadrature_demod_cf(samp_rate_out/(2*pi*fsk_deviation/2))
self.digital_pfb_clock_sync_xxx_0 = digital.pfb_clock_sync_fff(self.samples_per_symbol, 62.8e-3, (self.rrc_taps), self.nfilts, self.nfilts/2, 1.5, self.samples_per_symbol)
self.blocks_add_const_vxx_0 = blocks.add_const_vff((-1*threshold, ))
self.blocks_digital_binary_slicer_fb_0 = digital.binary_slicer_fb()
# flow for channel 1
self.blocks_tuning_filter_1 = filter.freq_xlating_fir_filter_ccc(int(samp_rate_in/samp_rate_out),
(self.firdes_taps),
tune_freq1-center_freq,
samp_rate_in)
self.analog_pwr_squelch_xx_1 = analog.pwr_squelch_cc(fskSquelch, 1, 1, False)
self.blocks_quadrature_demod_1 = analog.quadrature_demod_cf(samp_rate_out/(2*pi*fsk_deviation/2))
self.digital_pfb_clock_sync_xxx_1 = digital.pfb_clock_sync_fff(self.samples_per_symbol, 62.8e-3, (self.rrc_taps), self.nfilts, self.nfilts/2, 1.5, self.samples_per_symbol)
self.blocks_add_const_vxx_1 = blocks.add_const_vff((-1*threshold, ))
self.blocks_digital_binary_slicer_fb_1 = digital.binary_slicer_fb()
# flow for channel 2
self.blocks_tuning_filter_2 = filter.freq_xlating_fir_filter_ccc(int(samp_rate_in/samp_rate_out),
(self.firdes_taps),
tune_freq2-center_freq,
samp_rate_in)
self.analog_pwr_squelch_xx_2 = analog.pwr_squelch_cc(fskSquelch, 1, 1, False)
self.blocks_quadrature_demod_2 = analog.quadrature_demod_cf(samp_rate_out/(2*pi*fsk_deviation/2))
include_pfb = False
self.digital_pfb_clock_sync_xxx_2 = digital.pfb_clock_sync_fff(self.samples_per_symbol, 62.8e-3, (self.rrc_taps), self.nfilts, self.nfilts/2, 1.5, self.samples_per_symbol)
self.blocks_add_const_vxx_2 = blocks.add_const_vff((-1*threshold, ))
self.blocks_digital_binary_slicer_fb_2 = digital.binary_slicer_fb()
# these are high during idle times, so we need to combine the three channel outputs logically with an and function
self.blocks_and_xx_0 = blocks.and_bb()
# swapped message sink for file sink
#self.blocks_file_sink_0 = blocks.file_sink(gr.sizeof_char*1, dig_out_filename, False)
#self.blocks_file_sink_0.set_unbuffered(False)
self.sink_queue = gr.msg_queue()
self.blocks_message_sink_0 = blocks.message_sink(gr.sizeof_char*1, self.sink_queue, False)
##################################################
# Connections
##################################################
# channel 0
self.connect((self.blocks_file_source_0, 0), (self.blocks_tuning_filter_0, 0))
self.connect((self.blocks_tuning_filter_0, 0), (self.analog_pwr_squelch_xx_0, 0))
self.connect((self.analog_pwr_squelch_xx_0, 0), (self.blocks_quadrature_demod_0, 0))
self.connect((self.blocks_quadrature_demod_0, 0), (self.digital_pfb_clock_sync_xxx_0, 0))
self.connect((self.digital_pfb_clock_sync_xxx_0, 0), (self.blocks_add_const_vxx_0, 0))
#self.connect((self.blocks_quadrature_demod_0, 0), (self.blocks_add_const_vxx_0, 0))
self.connect((self.blocks_add_const_vxx_0, 0), (self.blocks_digital_binary_slicer_fb_0, 0))
# channel 1
self.connect((self.blocks_file_source_0, 0), (self.blocks_tuning_filter_1, 0))
self.connect((self.blocks_tuning_filter_1, 0), (self.analog_pwr_squelch_xx_1, 0))
self.connect((self.analog_pwr_squelch_xx_1, 0), (self.blocks_quadrature_demod_1, 0))
self.connect((self.blocks_quadrature_demod_1, 0), (self.digital_pfb_clock_sync_xxx_1, 0))
self.connect((self.digital_pfb_clock_sync_xxx_1, 0), (self.blocks_add_const_vxx_1, 0))
#self.connect((self.blocks_quadrature_demod_1, 0), (self.blocks_add_const_vxx_1, 0))
self.connect((self.blocks_add_const_vxx_1, 0), (self.blocks_digital_binary_slicer_fb_1, 0))
# channel 2
self.connect((self.blocks_file_source_0, 0), (self.blocks_tuning_filter_2, 0))
self.connect((self.blocks_tuning_filter_2, 0), (self.analog_pwr_squelch_xx_2, 0))
self.connect((self.analog_pwr_squelch_xx_2, 0), (self.blocks_quadrature_demod_2, 0))
self.connect((self.blocks_quadrature_demod_2, 0), (self.digital_pfb_clock_sync_xxx_2, 0))
self.connect((self.digital_pfb_clock_sync_xxx_2, 0), (self.blocks_add_const_vxx_2, 0))
#self.connect((self.blocks_quadrature_demod_2, 0), (self.blocks_add_const_vxx_2, 0))
self.connect((self.blocks_add_const_vxx_2, 0), (self.blocks_digital_binary_slicer_fb_2, 0))
# and gate
self.connect((self.blocks_digital_binary_slicer_fb_0, 0), (self.blocks_and_xx_0, 0))
self.connect((self.blocks_digital_binary_slicer_fb_1, 0), (self.blocks_and_xx_0, 1))
self.connect((self.blocks_digital_binary_slicer_fb_2, 0), (self.blocks_and_xx_0, 2))
#self.connect((self.digital_binary_slicer_fb_0, 0), (self.blocks_file_sink_0, 0))
# output to message sink
self.connect((self.blocks_and_xx_0, 0), (self.blocks_message_sink_0, 0))
