diff options
| -rw-r--r-- | gr-digital/python/generic_mod_demod.py | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/gr-digital/python/generic_mod_demod.py b/gr-digital/python/generic_mod_demod.py index da8e2cfd9..9378e2d61 100644 --- a/gr-digital/python/generic_mod_demod.py +++ b/gr-digital/python/generic_mod_demod.py @@ -265,8 +265,9 @@ class generic_demod(gr.hier_block2): self.agc = gr.agc2_cc(0.6e-1, 1e-3, 1, 1, 100) # Frequency correction + fll_ntaps = 55 self.freq_recov = digital_swig.fll_band_edge_cc(self._samples_per_symbol, self._excess_bw, - ntaps, self._freq_bw) + fll_ntaps, self._freq_bw) # symbol timing recovery with RRC data filter taps = gr.firdes.root_raised_cosine(nfilts, nfilts*self._samples_per_symbol, @@ -275,6 +276,9 @@ class generic_demod(gr.hier_block2): self._timing_bw, taps, nfilts, nfilts//2, self._timing_max_dev) + # Perform phase / fine frequency correction + self.phase_recov = digital_swig.costas_loop_cc(self._phase_bw, arity) + fmin = -0.25 fmax = 0.25 self.receiver = digital_swig.constellation_receiver_cb( @@ -283,7 +287,8 @@ class generic_demod(gr.hier_block2): # Do differential decoding based on phase change of symbols if differential: - self.diffdec = gr.diff_decoder_bb(arity) + #self.diffdec = gr.diff_decoder_bb(arity) + self.diffdec = gr.diff_phasor_cc() if self._constellation.apply_pre_diff_code(): self.symbol_mapper = gr.map_bb( @@ -292,16 +297,23 @@ class generic_demod(gr.hier_block2): # unpack the k bit vector into a stream of bits self.unpack = gr.unpack_k_bits_bb(self.bits_per_symbol()) + p = 1*math.pi/4.0 + c = complex(math.sin(p), math.cos(p)) + self.rotate = gr.multiply_const_cc(c) + if verbose: self._print_verbage() if log: self._setup_logging() - + # Connect and Initialize base class - blocks = [self, self.agc, self.freq_recov, self.time_recov, self.receiver] + blocks = [self, self.agc, self.freq_recov, self.time_recov] if differential: blocks.append(self.diffdec) + blocks.append(self.rotate) + blocks.append(self.receiver) + if self._constellation.apply_pre_diff_code(): blocks.append(self.symbol_mapper) blocks += [self.unpack, self] @@ -351,7 +363,8 @@ class generic_demod(gr.hier_block2): gr.file_sink(gr.sizeof_float, "rx_receiver_freq.32f")) if self._differential: self.connect(self.diffdec, - gr.file_sink(gr.sizeof_char, "rx_diffdec.8b")) + gr.file_sink(gr.sizeof_gr_complex, "rx_diffdec.8b")) + #gr.file_sink(gr.sizeof_char, "rx_diffdec.8b")) if self._constellation.apply_pre_diff_code(): self.connect(self.symbol_mapper, gr.file_sink(gr.sizeof_char, "rx_symbol_mapper.8b")) |