def __init__(self):
gr.top_block.__init__(self)
self._nsamples = 1000000
self._audio_rate = 8000
# Set up N channels with their own baseband and IF frequencies
self._N = 5
chspacing = 16000
freq = [10, 20, 30, 40, 50]
f_lo = [0, 1*chspacing, -1*chspacing, 2*chspacing, -2*chspacing]
self._if_rate = 4*self._N*self._audio_rate
# Create a signal source and frequency modulate it
self.sum = gr.add_cc ()
for n in xrange(self._N):
sig = gr.sig_source_f(self._audio_rate, gr.GR_SIN_WAVE, freq[n], 0.5)
fm = fmtx(f_lo[n], self._audio_rate, self._if_rate)
self.connect(sig, fm)
self.connect(fm, (self.sum, n))
self.head = gr.head(gr.sizeof_gr_complex, self._nsamples)
self.snk_tx = gr.vector_sink_c()
self.channel = blks2.channel_model(0.1)
self.connect(self.sum, self.head, self.channel, self.snk_tx)
# Design the channlizer
self._M = 10
bw = chspacing/2.0
t_bw = chspacing/10.0
self._chan_rate = self._if_rate / self._M
self._taps = gr.firdes.low_pass_2(1, self._if_rate, bw, t_bw,
attenuation_dB=100,
window=gr.firdes.WIN_BLACKMAN_hARRIS)
tpc = math.ceil(float(len(self._taps)) / float(self._M))
print "Number of taps: ", len(self._taps)
print "Number of channels: ", self._M
print "Taps per channel: ", tpc
self.pfb = blks2.pfb_channelizer_ccf(self._M, self._taps)
self.connect(self.channel, self.pfb)
# Create a file sink for each of M output channels of the filter and connect it
self.fmdet = list()
self.squelch = list()
self.snks = list()
for i in xrange(self._M):
self.fmdet.append(blks2.nbfm_rx(self._audio_rate, self._chan_rate))
self.squelch.append(blks2.standard_squelch(self._audio_rate*10))
self.snks.append(gr.vector_sink_f())
self.connect((self.pfb, i), self.fmdet[i], self.squelch[i], self.snks[i])
def __init__(self):
gr.top_block.__init__(self)
self._nsamples = 1000000
self._audio_rate = 8000
# Set up N channels with their own baseband and IF frequencies
self._N = 5
chspacing = 16000
freq = [10, 20, 30, 40, 50]
f_lo = [0, 1*chspacing, -1*chspacing, 2*chspacing, -2*chspacing]
self._if_rate = 4*self._N*self._audio_rate
# Create a signal source and frequency modulate it
self.sum = gr.add_cc ()
for n in xrange(self._N):
sig = gr.sig_source_f(self._audio_rate, gr.GR_SIN_WAVE, freq[n], 0.5)
fm = fmtx(f_lo[n], self._audio_rate, self._if_rate)
self.connect(sig, fm)
self.connect(fm, (self.sum, n))
self.head = gr.head(gr.sizeof_gr_complex, self._nsamples)
self.snk_tx = gr.vector_sink_c()
self.channel = blks2.channel_model(0.1)
self.connect(self.sum, self.head, self.channel, self.snk_tx)
# Design the channlizer
self._M = 10
bw = chspacing/2.0
t_bw = chspacing/10.0
self._chan_rate = self._if_rate / self._M
self._taps = gr.firdes.low_pass_2(1, self._if_rate, bw, t_bw,
attenuation_dB=100,
window=gr.firdes.WIN_BLACKMAN_hARRIS)
tpc = math.ceil(float(len(self._taps)) / float(self._M))
print "Number of taps: ", len(self._taps)
print "Number of channels: ", self._M
print "Taps per channel: ", tpc
self.pfb = blks2.pfb_channelizer_ccf(self._M, self._taps)
self.connect(self.channel, self.pfb)
# Create a file sink for each of M output channels of the filter and connect it
self.fmdet = list()
self.squelch = list()
self.snks = list()
for i in xrange(self._M):
self.fmdet.append(blks2.nbfm_rx(self._audio_rate, self._chan_rate))
self.squelch.append(blks2.standard_squelch(self._audio_rate*10))
self.snks.append(gr.vector_sink_f())
self.connect((self.pfb, i), self.fmdet[i], self.squelch[i], self.snks[i])
def setup_flowgraph(self, mode, ber_skipbytes=0): # parameters self.dp.set_mode(mode) self.rp.set_mode(mode) self.vlen = self.dp.num_carriers/4 self.ber_skipbytes = ber_skipbytes # trigger signals frame_trigger = [1]+[0]*(self.dp.symbols_per_frame-2) self.frame_start = frame_trigger*(len(self.random_bytes)/(self.vlen*(self.dp.symbols_per_frame-1)))+frame_trigger[0:(len(self.random_bytes)/self.vlen)%(self.dp.symbols_per_frame-1)] # sources/sinks self.source = gr.vector_source_b(self.random_bytes, False) self.trig = gr.vector_source_b(self.frame_start, False) if self.ber_sink: self.sink = dab.blocks.measure_ber_b() else: self.sink = gr.vector_sink_b() self.trig_sink = gr.null_sink(gr.sizeof_char) # self.noise_start = gr.noise_source_c(gr.GR_GAUSSIAN, math.sqrt(2), random.randint(0,10000)) # self.noise_start_head = gr.head(gr.sizeof_gr_complex, NOISE_SAMPLES_AT_START) # self.noise_end = gr.noise_source_c(gr.GR_GAUSSIAN, math.sqrt(2), random.randint(0,10000)) # self.noise_end_head = gr.head(gr.sizeof_gr_complex, NOISE_SAMPLES_AT_END) # blocks self.s2v = gr.stream_to_vector(gr.sizeof_char, self.vlen) self.v2s = gr.vector_to_stream(gr.sizeof_char, self.vlen) if self.ber_sink: self.ber_skipbytes0 = gr.skiphead(gr.sizeof_char, self.ber_skipbytes) self.ber_skipbytes1 = gr.skiphead(gr.sizeof_char, self.ber_skipbytes+self.dp.bytes_per_frame) # more blocks (they have state, so better reinitialise them) self.mod = dab.ofdm_mod(self.dp, debug = False) self.rescale = gr.multiply_const_cc(1) self.amp = gr.multiply_const_cc(1) self.channel = blks2.channel_model(noise_voltage=0, noise_seed=random.randint(0,10000)) # self.cat = dab.concatenate_signals(gr.sizeof_gr_complex) self.demod = dab.ofdm_demod(self.dp, self.rp, debug = False, verbose = True) # connect it all if self.ber_sink: self.connect(self.source, self.s2v, (self.mod,0), self.rescale, self.amp, self.channel, (self.demod,0), self.v2s, self.ber_skipbytes0, self.sink) self.connect(self.source, self.ber_skipbytes1, (self.sink,1)) else: self.connect(self.source, self.s2v, (self.mod,0), self.rescale, self.amp, self.channel, (self.demod,0), self.v2s, self.sink) self.connect(self.trig, (self.mod,1)) self.connect((self.demod, 1), self.trig_sink) # SNR calculation and prober self.probe_signal = gr.probe_avg_mag_sqrd_c(0,0.00001) self.probe_total = gr.probe_avg_mag_sqrd_c(0,0.00001) self.connect(self.amp, self.probe_signal) self.connect(self.channel, self.probe_total)
def setup_flowgraph(self, mode, ber_skipbytes=0):
# parameters
self.dp.set_mode(mode)
self.rp.set_mode(mode)
self.vlen = self.dp.num_carriers / 4
self.ber_skipbytes = ber_skipbytes
# trigger signals
frame_trigger = [1] + [0] * (self.dp.symbols_per_frame - 2)
self.frame_start = frame_trigger * (
len(self.random_bytes) / (self.vlen *
(self.dp.symbols_per_frame - 1))
) + frame_trigger[0:(len(self.random_bytes) / self.vlen) %
(self.dp.symbols_per_frame - 1)]
# sources/sinks
self.source = gr.vector_source_b(self.random_bytes, False)
self.trig = gr.vector_source_b(self.frame_start, False)
if self.ber_sink:
self.sink = grdab.blocks.measure_ber_b()
else:
self.sink = gr.vector_sink_b()
# self.noise_start = gr.noise_source_c(gr.GR_GAUSSIAN, math.sqrt(2), random.randint(0,10000))
# self.noise_start_head = gr.head(gr.sizeof_gr_complex, NOISE_SAMPLES_AT_START)
# self.noise_end = gr.noise_source_c(gr.GR_GAUSSIAN, math.sqrt(2), random.randint(0,10000))
# self.noise_end_head = gr.head(gr.sizeof_gr_complex, NOISE_SAMPLES_AT_END)
# blocks
self.s2v = gr.stream_to_vector(gr.sizeof_char, self.vlen)
self.v2s = gr.vector_to_stream(gr.sizeof_char, self.vlen)
if self.ber_sink:
self.ber_skipbytes0 = gr.skiphead(gr.sizeof_char,
self.ber_skipbytes)
self.ber_skipbytes1 = gr.skiphead(
gr.sizeof_char, self.ber_skipbytes + self.dp.bytes_per_frame)
# more blocks (they have state, so better reinitialise them)
self.mod = grdab.ofdm_mod(self.dp, debug=False)
self.rescale = gr.multiply_const_cc(1)
self.amp = gr.multiply_const_cc(1)
self.channel = blks2.channel_model(noise_voltage=0,
noise_seed=random.randint(0, 10000))
# self.cat = grdab.concatenate_signals(gr.sizeof_gr_complex)
self.demod = grdab.ofdm_demod(self.dp,
self.rp,
debug=False,
verbose=True)
# connect it all
if self.ber_sink:
self.connect(self.source, self.s2v, (self.mod, 0), self.rescale,
self.amp, self.channel, (self.demod, 0), self.v2s,
self.ber_skipbytes0, self.sink)
self.connect(self.source, self.ber_skipbytes1, (self.sink, 1))
else:
self.connect(self.source, self.s2v, (self.mod, 0), self.rescale,
self.amp, self.channel, (self.demod, 0), self.v2s,
self.sink)
self.connect(self.trig, (self.mod, 1))
# SNR calculation and prober
self.probe_signal = gr.probe_avg_mag_sqrd_c(0, 0.00001)
self.probe_total = gr.probe_avg_mag_sqrd_c(0, 0.00001)
self.connect(self.amp, self.probe_signal)
self.connect(self.channel, self.probe_total)
