def __init__(self, bitrate,
constellation, samples_per_symbol,
differential, excess_bw, gray_coded,
freq_bw, timing_bw, phase_bw,
verbose, log):
gr.hier_block2.__init__(self, "bert_receive",
gr.io_signature(1, 1, gr.sizeof_gr_complex), # Input signature
gr.io_signature(0, 0, 0)) # Output signature
self._bitrate = bitrate
self._demod = digital.generic_demod(constellation, differential,
samples_per_symbol,
gray_coded, excess_bw,
freq_bw, timing_bw, phase_bw,
verbose, log)
self._symbol_rate = self._bitrate / self._demod.bits_per_symbol()
self._sample_rate = self._symbol_rate * samples_per_symbol
# Add an SNR probe on the demodulated constellation
self._snr_probe = digital.probe_mpsk_snr_est_c(digital.SNR_EST_M2M4, 1000,
alpha=10.0/self._symbol_rate)
self.connect(self._demod.time_recov, self._snr_probe)
# Descramble BERT sequence. A channel error will create 3 incorrect bits
self._descrambler = digital.descrambler_bb(0x8A, 0x7F, 7) # CCSDS 7-bit descrambler
# Measure BER by the density of 0s in the stream
self._ber = digital.probe_density_b(1.0/self._symbol_rate)
self.connect(self, self._demod, self._descrambler, self._ber)
def __init__(self, bitrate, constellation, samples_per_symbol,
differential, excess_bw, gray_coded, freq_bw, timing_bw,
phase_bw, verbose, log):
gr.hier_block2.__init__(
self,
"bert_receive",
gr.io_signature(1, 1, gr.sizeof_gr_complex), # Input signature
gr.io_signature(0, 0, 0)) # Output signature
self._bitrate = bitrate
self._demod = digital.generic_demod(constellation, differential,
samples_per_symbol, gray_coded,
excess_bw, freq_bw, timing_bw,
phase_bw, verbose, log)
self._symbol_rate = self._bitrate / self._demod.bits_per_symbol()
self._sample_rate = self._symbol_rate * samples_per_symbol
# Add an SNR probe on the demodulated constellation
self._snr_probe = digital.probe_mpsk_snr_est_c(digital.SNR_EST_M2M4,
1000,
alpha=10.0 /
self._symbol_rate)
self.connect(self._demod.time_recov, self._snr_probe)
# Descramble BERT sequence. A channel error will create 3 incorrect bits
self._descrambler = digital.descrambler_bb(
0x8A, 0x7F, 7) # CCSDS 7-bit descrambler
# Measure BER by the density of 0s in the stream
self._ber = digital.probe_density_b(1.0 / self._symbol_rate)
self.connect(self, self._demod, self._descrambler, self._ber)