def test_000(self):
N = 1000 # number of samples to use
M = 5 # Number of channels
fs = 1000 # baseband sampling rate
ifs = M * fs # input samp rate to decimator
channel = 0 # Extract channel 0
taps = filter.firdes.low_pass_2(
1,
ifs,
fs / 2,
fs / 10,
attenuation_dB=80,
window=filter.firdes.WIN_BLACKMAN_hARRIS)
signals = list()
add = blocks.add_cc()
freqs = [-200, -100, 0, 100, 200]
for i in xrange(len(freqs)):
f = freqs[i] + (M / 2 - M + i + 1) * fs
data = sig_source_c(ifs, f, 1, N)
signals.append(blocks.vector_source_c(data))
self.tb.connect(signals[i], (add, i))
head = blocks.head(gr.sizeof_gr_complex, N)
s2ss = blocks.stream_to_streams(gr.sizeof_gr_complex, M)
pfb = filter.pfb_decimator_ccf(M, taps, channel)
snk = blocks.vector_sink_c()
self.tb.connect(add, head, s2ss)
for i in xrange(M):
self.tb.connect((s2ss, i), (pfb, i))
self.tb.connect(pfb, snk)
self.tb.run()
Ntest = 50
L = len(snk.data())
t = map(lambda x: float(x) / fs, xrange(L))
# Create known data as complex sinusoids for the baseband freq
# of the extracted channel is due to decimator output order.
phase = 0
expected_data = map(lambda x: math.cos(2.*math.pi*freqs[2]*x+phase) + \
1j*math.sin(2.*math.pi*freqs[2]*x+phase), t)
dst_data = snk.data()
self.assertComplexTuplesAlmostEqual(expected_data[-Ntest:],
dst_data[-Ntest:], 4)
def __init__(self,
decim,
taps=None,
channel=0,
atten=100,
use_fft_rotators=True,
use_fft_filters=True):
gr.hier_block2.__init__(self, "pfb_decimator_ccf",
gr.io_signature(1, 1, gr.sizeof_gr_complex),
gr.io_signature(1, 1, gr.sizeof_gr_complex))
self._decim = decim
self._channel = channel
if (taps is not None) and (len(taps) > 0):
self._taps = taps
else:
# Create a filter that covers the full bandwidth of the input signal
bw = 0.4
tb = 0.2
ripple = 0.1
made = False
while not made:
try:
self._taps = optfir.low_pass(1, self._decim, bw, bw + tb,
ripple, atten)
made = True
except RuntimeError:
ripple += 0.01
made = False
print(
"Warning: set ripple to %.4f dB. If this is a problem, adjust the attenuation or create your own filter taps."
% (ripple))
# Build in an exit strategy; if we've come this far, it ain't working.
if (ripple >= 1.0):
raise RuntimeError(
"optfir could not generate an appropriate filter.")
self.s2ss = blocks.stream_to_streams(gr.sizeof_gr_complex, self._decim)
self.pfb = filter.pfb_decimator_ccf(self._decim, self._taps,
self._channel, use_fft_rotators,
use_fft_filters)
self.connect(self, self.s2ss)
for i in xrange(self._decim):
self.connect((self.s2ss, i), (self.pfb, i))
self.connect(self.pfb, self)
def test_000(self):
N = 1000 # number of samples to use
M = 5 # Number of channels
fs = 1000 # baseband sampling rate
ifs = M * fs # input samp rate to decimator
channel = 0 # Extract channel 0
taps = filter.firdes.low_pass_2(
1, ifs, fs / 2, fs / 10, attenuation_dB=80, window=filter.firdes.WIN_BLACKMAN_hARRIS
)
signals = list()
add = gr.add_cc()
freqs = [-200, -100, 0, 100, 200]
for i in xrange(len(freqs)):
f = freqs[i] + (M / 2 - M + i + 1) * fs
signals.append(gr.sig_source_c(ifs, gr.GR_SIN_WAVE, f, 1))
self.tb.connect(signals[i], (add, i))
head = gr.head(gr.sizeof_gr_complex, N)
s2ss = gr.stream_to_streams(gr.sizeof_gr_complex, M)
pfb = filter.pfb_decimator_ccf(M, taps, channel)
snk = gr.vector_sink_c()
self.tb.connect(add, head, s2ss)
for i in xrange(M):
self.tb.connect((s2ss, i), (pfb, i))
self.tb.connect(pfb, snk)
self.tb.run()
Ntest = 50
L = len(snk.data())
t = map(lambda x: float(x) / fs, xrange(L))
# Create known data as complex sinusoids for the baseband freq
# of the extracted channel is due to decimator output order.
phase = 0
expected_data = map(
lambda x: math.cos(2.0 * math.pi * freqs[2] * x + phase)
+ 1j * math.sin(2.0 * math.pi * freqs[2] * x + phase),
t,
)
dst_data = snk.data()
self.assertComplexTuplesAlmostEqual(expected_data[-Ntest:], dst_data[-Ntest:], 4)
def __init__(self, decim, taps=None, channel=0, atten=100,
use_fft_rotators=True, use_fft_filters=True):
gr.hier_block2.__init__(self, "pfb_decimator_ccf",
gr.io_signature(1, 1, gr.sizeof_gr_complex),
gr.io_signature(1, 1, gr.sizeof_gr_complex))
self._decim = decim
self._channel = channel
if (taps is not None) and (len(taps) > 0):
self._taps = taps
else:
# Create a filter that covers the full bandwidth of the input signal
bw = 0.4
tb = 0.2
ripple = 0.1
made = False
while not made:
try:
self._taps = optfir.low_pass(1, self._decim, bw, bw+tb, ripple, atten)
made = True
except RuntimeError:
ripple += 0.01
made = False
print("Warning: set ripple to %.4f dB. If this is a problem, adjust the attenuation or create your own filter taps." % (ripple))
# Build in an exit strategy; if we've come this far, it ain't working.
if(ripple >= 1.0):
raise RuntimeError("optfir could not generate an appropriate filter.")
self.s2ss = blocks.stream_to_streams(gr.sizeof_gr_complex, self._decim)
self.pfb = filter.pfb_decimator_ccf(self._decim, self._taps, self._channel,
use_fft_rotators, use_fft_filters)
self.connect(self, self.s2ss)
for i in xrange(self._decim):
self.connect((self.s2ss,i), (self.pfb,i))
self.connect(self.pfb, self)
