def test_icapture():
x = range(100)
y = []
z = []
for i in common.icapture(x, result=y):
z.append(i)
assert x == y
assert x == z
def demodulate(symbols, filters, freqs, sampler):
streams = []
symbol_list = []
errors = {}
def error_handler(received, decoded, freq):
errors.setdefault(freq, []).append(received / decoded)
generators = common.split(symbols, n=len(freqs))
for freq, S in zip(freqs, generators):
S = filters[freq](S)
if pylab:
equalized = []
S = common.icapture(S, result=equalized)
symbol_list.append(equalized)
freq_handler = functools.partial(error_handler, freq=freq)
bits = modem.qam.decode(S, freq_handler) # list of bit tuples
streams.append(bits) # stream per frequency
stats['symbol_list'] = symbol_list
stats['rx_bits'] = 0
stats['rx_start'] = time.time()
log.info('Demodulation started')
for i, block in enumerate(itertools.izip(*streams)): # block per frequency
for bits in block:
stats['rx_bits'] = stats['rx_bits'] + len(bits)
yield bits
if i and i % config.baud == 0:
mean_err = np.array([e for v in errors.values() for e in v])
correction = np.mean(np.angle(mean_err)) / (2*np.pi)
duration = time.time() - stats['rx_start']
log.debug('%10.1f kB, realtime: %6.2f%%, sampling error: %+.3f%%',
stats['rx_bits'] / 8e3,
duration * 100.0 / (i*config.Tsym),
correction * 1e2)
errors.clear()
sampler.freq -= 0.01 * correction / config.Fc
sampler.offset -= correction
