diff options
Diffstat (limited to 'gr-digital/python/digital/cpm.py')
| -rw-r--r-- | gr-digital/python/digital/cpm.py | 69 |
1 files changed, 36 insertions, 33 deletions
diff --git a/gr-digital/python/digital/cpm.py b/gr-digital/python/digital/cpm.py index d21ae55a87..ca32fb7036 100644 --- a/gr-digital/python/digital/cpm.py +++ b/gr-digital/python/digital/cpm.py @@ -29,7 +29,7 @@ _def_samples_per_symbol = 2 _def_bits_per_symbol = 1 _def_h_numerator = 1 _def_h_denominator = 2 -_def_cpm_type = 0 # 0=CPFSK, 1=GMSK, 2=RC, 3=GENERAL +_def_cpm_type = 0 # 0=CPFSK, 1=GMSK, 2=RC, 3=GENERAL _def_bt = 0.35 _def_symbols_per_pulse = 1 _def_generic_taps = numpy.empty(1) @@ -80,62 +80,69 @@ class cpm_mod(gr.hier_block2): log=_def_log): gr.hier_block2.__init__(self, "cpm_mod", - gr.io_signature(1, 1, gr.sizeof_char), # Input signature - gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature + # Input signature + gr.io_signature(1, 1, gr.sizeof_char), + gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature self._samples_per_symbol = samples_per_symbol self._bits_per_symbol = bits_per_symbol self._h_numerator = h_numerator self._h_denominator = h_denominator self._cpm_type = cpm_type - self._bt=bt - if cpm_type == 0 or cpm_type == 2 or cpm_type == 3: # CPFSK, RC, Generic + self._bt = bt + if cpm_type == 0 or cpm_type == 2 or cpm_type == 3: # CPFSK, RC, Generic self._symbols_per_pulse = symbols_per_pulse - elif cpm_type == 1: # GMSK + elif cpm_type == 1: # GMSK self._symbols_per_pulse = 4 else: - raise TypeError("cpm_type must be an integer in {0,1,2,3}, is %r" % (cpm_type,)) + raise TypeError( + "cpm_type must be an integer in {0,1,2,3}, is %r" % (cpm_type,)) - self._generic_taps=numpy.array(generic_taps) + self._generic_taps = numpy.array(generic_taps) if samples_per_symbol < 2: - raise TypeError("samples_per_symbol must be >= 2, is %r" % (samples_per_symbol,)) + raise TypeError("samples_per_symbol must be >= 2, is %r" % + (samples_per_symbol,)) self.nsymbols = 2**bits_per_symbol - self.sym_alphabet = numpy.arange(-(self.nsymbols-1),self.nsymbols,2).tolist() - + self.sym_alphabet = numpy.arange(-(self.nsymbols - 1), + self.nsymbols, 2).tolist() self.ntaps = int(self._symbols_per_pulse * samples_per_symbol) sensitivity = 2 * pi * h_numerator / h_denominator / samples_per_symbol # Unpack Bytes into bits_per_symbol groups - self.B2s = blocks.packed_to_unpacked_bb(bits_per_symbol,gr.GR_MSB_FIRST) - + self.B2s = blocks.packed_to_unpacked_bb( + bits_per_symbol, gr.GR_MSB_FIRST) # Turn it into symmetric PAM data. - self.pam = digital_python.chunks_to_symbols_bf(self.sym_alphabet,1) + self.pam = digital_python.chunks_to_symbols_bf(self.sym_alphabet, 1) # Generate pulse (sum of taps = samples_per_symbol/2) - if cpm_type == 0: # CPFSK - self.taps= (1.0/self._symbols_per_pulse/2,) * self.ntaps - elif cpm_type == 1: # GMSK + if cpm_type == 0: # CPFSK + self.taps = (1.0 / self._symbols_per_pulse / 2,) * self.ntaps + elif cpm_type == 1: # GMSK gaussian_taps = filter.firdes.gaussian( 1.0 / 2, # gain samples_per_symbol, # symbol_rate bt, # bandwidth * symbol time self.ntaps # number of taps - ) + ) sqwave = (1,) * samples_per_symbol # rectangular window - self.taps = numpy.convolve(numpy.array(gaussian_taps),numpy.array(sqwave)) - elif cpm_type == 2: # Raised Cosine + self.taps = numpy.convolve(numpy.array( + gaussian_taps), numpy.array(sqwave)) + elif cpm_type == 2: # Raised Cosine # generalize it for arbitrary roll-off factor - self.taps = (1-numpy.cos(2*pi*numpy.arange(0 / self.ntaps/samples_per_symbol/self._symbols_per_pulse)),(2*self._symbols_per_pulse)) - elif cpm_type == 3: # Generic CPM + self.taps = (1 - numpy.cos(2 * pi * numpy.arange(0 / self.ntaps / + samples_per_symbol / self._symbols_per_pulse)), (2 * self._symbols_per_pulse)) + elif cpm_type == 3: # Generic CPM self.taps = generic_taps else: - raise TypeError("cpm_type must be an integer in {0,1,2,3}, is %r" % (cpm_type,)) + raise TypeError( + "cpm_type must be an integer in {0,1,2,3}, is %r" % (cpm_type,)) - self.filter = filter.pfb.arb_resampler_fff(samples_per_symbol, self.taps) + self.filter = filter.pfb.arb_resampler_fff( + samples_per_symbol, self.taps) # FM modulation self.fmmod = analog.frequency_modulator_fc(sensitivity) @@ -170,19 +177,17 @@ class cpm_mod(gr.hier_block2): def symbols_per_pulse(self): return self._symbols_per_pulse - def _print_verbage(self): print("Samples per symbol = %d" % self._samples_per_symbol) print("Bits per symbol = %d" % self._bits_per_symbol) - print("h = " , self._h_numerator , " / " , self._h_denominator) - print("Symbol alphabet = " , self.sym_alphabet) + print("h = ", self._h_numerator, " / ", self._h_denominator) + print("Symbol alphabet = ", self.sym_alphabet) print("Symbols per pulse = %d" % self._symbols_per_pulse) - print("taps = " , self.taps) + print("taps = ", self.taps) print("CPM type = %d" % self._cpm_type) if self._cpm_type == 1: - print("Gaussian filter BT = %.2f" % self._bt) - + print("Gaussian filter BT = %.2f" % self._bt) def _setup_logging(self): print("Modulation logging turned on.") @@ -209,8 +214,7 @@ class cpm_mod(gr.hier_block2): Given command line options, create dictionary suitable for passing to __init__ """ return modulation_utils.extract_kwargs_from_options(cpm_mod.__init__, - ('self',), options) - + ('self',), options) # ///////////////////////////////////////////////////////////////////////////// @@ -219,7 +223,6 @@ class cpm_mod(gr.hier_block2): # # Not yet implemented # - # # Add these to the mod/demod registry # |