def __init__(self, constellation, differential, rotation):
        if constellation.arity() > 256:
            # If this becomes limiting some of the blocks should be generalised so
            # that they can work with shorts and ints as well as chars.
            raise ValueError("Constellation cannot contain more than 256 points.")

	gr.hier_block2.__init__(self, "mod_demod",
				gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
				gr.io_signature(1, 1, gr.sizeof_char))       # Output signature

        arity = constellation.arity()

        # TX
        self.constellation = constellation
        self.differential = differential
        import weakref
        self.blocks = [weakref.proxy(self)]
        # We expect a stream of unpacked bits.
        # First step is to pack them.
        self.blocks.append(
            gr.unpacked_to_packed_bb(1, gr.GR_MSB_FIRST))
        # Second step we unpack them such that we have k bits in each byte where
        # each constellation symbol hold k bits.
        self.blocks.append(
            gr.packed_to_unpacked_bb(self.constellation.bits_per_symbol(),
                                     gr.GR_MSB_FIRST))
        # Apply any pre-differential coding
        # Gray-coding is done here if we're also using differential coding.
        if self.constellation.apply_pre_diff_code():
            self.blocks.append(gr.map_bb(self.constellation.pre_diff_code()))
        # Differential encoding.
        if self.differential:
            self.blocks.append(gr.diff_encoder_bb(arity))
        # Convert to constellation symbols.
        self.blocks.append(gr.chunks_to_symbols_bc(self.constellation.points(),
                                                   self.constellation.dimensionality()))
        # CHANNEL
        # Channel just consists of a rotation to check differential coding.
        if rotation is not None:
            self.blocks.append(gr.multiply_const_cc(rotation))

        # RX
        # Convert the constellation symbols back to binary values.
        self.blocks.append(digital_swig.constellation_decoder_cb(self.constellation.base()))
        # Differential decoding.
        if self.differential:
            self.blocks.append(gr.diff_decoder_bb(arity))
        # Decode any pre-differential coding.
        if self.constellation.apply_pre_diff_code():
            self.blocks.append(gr.map_bb(
                mod_codes.invert_code(self.constellation.pre_diff_code())))
        # unpack the k bit vector into a stream of bits            
        self.blocks.append(gr.unpack_k_bits_bb(
                self.constellation.bits_per_symbol()))
        # connect to block output
        check_index = len(self.blocks)
        self.blocks = self.blocks[:check_index]
        self.blocks.append(weakref.proxy(self))

        self.connect(*self.blocks)
Esempio n. 2
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    def __init__(self,
                 sps,               # Samples per symbol
                 excess_bw,         # RRC filter excess bandwidth (typically 0.35-0.5)
                 amplitude,         # DAC output level, 0-32767, typically 2000-8000
                 vector_source,   # Indicate if it's the infinite sequence of 1, or by use the code to change the amplitude
                 ):

            gr.hier_block2.__init__(self, "bpsk_modulator",
                                gr.io_signature(0, 0, 0),                    # Input signature
                                gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
            
            # Create BERT data bit stream	
            
            self.vector_source = vector_source
            
            self._scrambler = gr.scrambler_bb(0x8A, 0x7F, 31) # CCSDS 7-bit scrambler
            
            # Map to constellation
            self._constellation = [-1+0j, 1+0j]
            self._mapper = gr.chunks_to_symbols_bc(self._constellation)	
            
            # Create RRC with specified excess bandwidth
            taps = gr.firdes.root_raised_cosine(sps,  # Gain
					    sps,	    # Sampling rate
					    1.0,	    # Symbol rate
					    excess_bw,	    # Roll-off factor
					    11*sps)         # Number of taps
            
            self._rrc = gr.interp_fir_filter_ccf(sps,	    # Interpolation rate
					     taps)	    # FIR taps
            
            self.amp = gr.multiply_const_cc(amplitude)
            
            # Wire block inputs and outputs
            self.connect(self.vector_source, self._scrambler, self._mapper, self._rrc, self.amp, self)
Esempio n. 3
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    def __init__(self,
                 sps,          # Samples per symbol
                 excess_bw,    # RRC filter excess bandwidth (typically 0.35-0.5)
                 amplitude     # DAC output level, 0-32767, typically 2000-8000
                 ):

        gr.hier_block2.__init__(self, "transmit_path",
                                gr.io_signature(0, 0, 0),                    # Input signature
                                gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature

        # Create BERT data bit stream	
	self._bits = gr.vector_source_b([1,], True)      # Infinite stream of ones
        self._scrambler = gr.scrambler_bb(0x8A, 0x7F, 7) # CCSDS 7-bit scrambler

	# Map to constellation
	self._constellation = [-1+0j, 1+0j]
	self._mapper = gr.chunks_to_symbols_bc(self._constellation)	

	# Create RRC with specified excess bandwidth
	taps = gr.firdes.root_raised_cosine(sps*amplitude,  # Gain
					    sps,	    # Sampling rate
					    1.0,	    # Symbol rate
					    excess_bw,	    # Roll-off factor
					    11*sps)         # Number of taps

	self._rrc = gr.interp_fir_filter_ccf(sps,	    # Interpolation rate
					     taps)	    # FIR taps

        # Wire block inputs and outputs
        self.connect(self._bits, self._scrambler, self._mapper, self._rrc, self)
Esempio n. 4
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def key_factory(index):
    print "FACTORY CALLED index = %d"%(index);
    
    r = es.es_pyhandler();

    excess_bw = 0.5;
    sps = 4;
    amplitude = sig_amp;
    taps = gr.firdes.root_raised_cosine(sps*amplitude,  # Gain
                        sps,        # Sampling rate
                        1.0,        # Symbol rate
                        excess_bw,      # Roll-off factor
                        11*sps)         # Number of taps

    blocks = {};
    blocks["src"] = es.vector_source([1]) 
    blocks["scrambler"] = gr.scrambler_bb(0x8A, 0x7F, 7);
    blocks["mapper"] = gr.chunks_to_symbols_bc( [-1+0j, 0+1j, 1+0j, 0-1j] );
    blocks["rrc"] = gr.interp_fir_filter_ccf(sps, taps);
    r.sink = es.vector_sink([gr.sizeof_gr_complex]);
    r.set_pyb2(blocks);

    tb  = gr.top_block();
    tb.connect( blocks["src"], blocks["scrambler"], blocks["mapper"], blocks["rrc"], r.sink );

    r.tb = tb.to_top_block();
    return r;
Esempio n. 5
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    def __init__(self, sample_rate, symbol_rate):
        gr.hier_block2.__init__(
            self,
            "dvb_s_modulator_bc",
            gr.io_signature(1, 1, gr.sizeof_char),  # Input signature
            gr.io_signature(1, 1, gr.sizeof_gr_complex))  # Output signature

        samples_per_symbol = sample_rate / symbol_rate
        if samples_per_symbol < 2:
            raise TypeError, "Samples per symbol must be >= 2"

        # Form symbols with 2 bits per symbol
        self.pack = gr.unpacked_to_packed_bb(1, gr.GR_MSB_FIRST)
        self.reunpack = gr.packed_to_unpacked_bb(2, gr.GR_MSB_FIRST)

        self.mapper = gr.chunks_to_symbols_bc(mod_constellation)

        # Design FIR filter taps for square root raised cosine filter
        ntaps = 11 * int(samples_per_symbol * nfilts)
        rrc_taps = gr.firdes.root_raised_cosine(nfilts, nfilts, 1.0,
                                                dvb_swig.RRC_ROLLOFF_FACTOR,
                                                ntaps)
        # Baseband pulse shaping filter
        self.rrc_filter = gr.pfb_arb_resampler_ccf(samples_per_symbol,
                                                   rrc_taps)

        self.connect(self, self.pack, self.reunpack, self.mapper,
                     self.rrc_filter, self)
Esempio n. 6
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    def __init__(self, constellation, differential, rotation):
        if constellation.arity() > 256:
            # If this becomes limiting some of the blocks should be generalised so
            # that they can work with shorts and ints as well as chars.
            raise ValueError("Constellation cannot contain more than 256 points.")

	gr.hier_block2.__init__(self, "mod_demod",
				gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
				gr.io_signature(1, 1, gr.sizeof_char))       # Output signature

        arity = constellation.arity()

        # TX
        self.constellation = constellation
        self.differential = differential
        self.blocks = [self]
        # We expect a stream of unpacked bits.
        # First step is to pack them.
        self.blocks.append(
            gr.unpacked_to_packed_bb(1, gr.GR_MSB_FIRST))
        # Second step we unpack them such that we have k bits in each byte where
        # each constellation symbol hold k bits.
        self.blocks.append(
            gr.packed_to_unpacked_bb(self.constellation.bits_per_symbol(),
                                     gr.GR_MSB_FIRST))
        # Apply any pre-differential coding
        # Gray-coding is done here if we're also using differential coding.
        if self.constellation.apply_pre_diff_code():
            self.blocks.append(gr.map_bb(self.constellation.pre_diff_code()))
        # Differential encoding.
        if self.differential:
            self.blocks.append(gr.diff_encoder_bb(arity))
        # Convert to constellation symbols.
        self.blocks.append(gr.chunks_to_symbols_bc(self.constellation.points(),
                                                   self.constellation.dimensionality()))
        # CHANNEL
        # Channel just consists of a rotation to check differential coding.
        if rotation is not None:
            self.blocks.append(gr.multiply_const_cc(rotation))

        # RX
        # Convert the constellation symbols back to binary values.
        self.blocks.append(digital_swig.constellation_decoder_cb(self.constellation.base()))
        # Differential decoding.
        if self.differential:
            self.blocks.append(gr.diff_decoder_bb(arity))
        # Decode any pre-differential coding.
        if self.constellation.apply_pre_diff_code():
            self.blocks.append(gr.map_bb(
                mod_codes.invert_code(self.constellation.pre_diff_code())))
        # unpack the k bit vector into a stream of bits            
        self.blocks.append(gr.unpack_k_bits_bb(
                self.constellation.bits_per_symbol()))
        # connect to block output
        check_index = len(self.blocks)
        self.blocks = self.blocks[:check_index]
        self.blocks.append(self)

        self.connect(*self.blocks)
Esempio n. 7
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def mod_bits_qpsk(strbits, syms=[0, 1, 3, 2], pts=[-1, 1j, 1, -1j]):
    src = gr.vector_source_b(es.string_to_vector(strbits))
    unpack = gr.packed_to_unpacked_bb(1, gr.GR_MSB_FIRST)
    pack = gr.pack_k_bits_bb(2)
    bts = gr.map_bb((syms))
    mapper = gr.chunks_to_symbols_bc(pts, 1)
    rrc_taps = gr.firdes.root_raised_cosine(1.0, 2.0, 1.0, 0.35, 91)
    interp = gr.interp_fir_filter_ccc(2, (rrc_taps))
    sink = gr.vector_sink_c()
    tb = gr.top_block()
    tb.connect(src, unpack, pack, bts, mapper, interp, sink)
    tb.run()
    return sink.data()
Esempio n. 8
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def mod_bits_qpsk(strbits, syms=[0,1,3,2], pts=[-1,1j,1,-1j]):
    src = gr.vector_source_b(es.string_to_vector(strbits));
    unpack = gr.packed_to_unpacked_bb(1, gr.GR_MSB_FIRST);
    pack = gr.pack_k_bits_bb(2);
    bts = gr.map_bb((syms));
    mapper =  gr.chunks_to_symbols_bc(pts, 1);
    rrc_taps = gr.firdes.root_raised_cosine(1.0, 2.0, 1.0, 0.35, 91);
    interp = gr.interp_fir_filter_ccc(2, (rrc_taps))
    sink = gr.vector_sink_c();
    tb=gr.top_block();
    tb.connect(src,unpack,pack,bts,mapper,interp,sink);
    tb.run();
    return sink.data();
Esempio n. 9
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 def __init__(self, EbN0):
     gr.top_block.__init__(self)
     self.const = digital.qpsk_constellation()
     # Source is N_BITS bits, non-repeated
     data = map(int, numpy.random.randint(0, self.const.arity(), N_BITS/self.const.bits_per_symbol()))
     src   = gr.vector_source_b(data, False)
     mod   = gr.chunks_to_symbols_bc((self.const.points()), 1)
     add   = gr.add_vcc()
     noise = gr.noise_source_c(gr.GR_GAUSSIAN,
                               self.EbN0_to_noise_voltage(EbN0),
                               RAND_SEED)
     demod = digital.constellation_decoder_cb(self.const.base())
     ber   = BitErrors(self.const.bits_per_symbol())
     self.sink  = gr.vector_sink_f()
     self.connect(src, mod, add, demod, ber, self.sink)
     self.connect(noise, (add, 1))
     self.connect(src, (ber, 1))
Esempio n. 10
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 def __init__(self, EbN0):
     gr.top_block.__init__(self)
     self.const = digital.qpsk_constellation()
     # Source is N_BITS bits, non-repeated
     data = map(
         int,
         numpy.random.randint(0, self.const.arity(),
                              N_BITS / self.const.bits_per_symbol()))
     src = gr.vector_source_b(data, False)
     mod = gr.chunks_to_symbols_bc((self.const.points()), 1)
     add = gr.add_vcc()
     noise = gr.noise_source_c(gr.GR_GAUSSIAN,
                               self.EbN0_to_noise_voltage(EbN0), RAND_SEED)
     demod = digital.constellation_decoder_cb(self.const.base())
     ber = BitErrors(self.const.bits_per_symbol())
     self.sink = gr.vector_sink_f()
     self.connect(src, mod, add, demod, ber, self.sink)
     self.connect(noise, (add, 1))
     self.connect(src, (ber, 1))
Esempio n. 11
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	def __init__(self, sample_rate, symbol_rate):
		gr.hier_block2.__init__(self, "dvb_s_modulator_bc",
				gr.io_signature(1, 1, gr.sizeof_char),			# Input signature
				gr.io_signature(1, 1, gr.sizeof_gr_complex))	# Output signature

		samples_per_symbol = sample_rate / symbol_rate
		if samples_per_symbol < 2:
			raise TypeError, "Samples per symbol must be >= 2"

		# Form symbols with 2 bits per symbol
		self.pack = gr.unpacked_to_packed_bb(1, gr.GR_MSB_FIRST)
		self.reunpack = gr.packed_to_unpacked_bb(2, gr.GR_MSB_FIRST)

		self.mapper = gr.chunks_to_symbols_bc(mod_constellation)

		# Design FIR filter taps for square root raised cosine filter
		ntaps = 11 * int(samples_per_symbol * nfilts)
		rrc_taps = gr.firdes.root_raised_cosine(nfilts, nfilts, 1.0, dvb_swig.RRC_ROLLOFF_FACTOR, ntaps)
		# Baseband pulse shaping filter
		self.rrc_filter = gr.pfb_arb_resampler_ccf(samples_per_symbol, rrc_taps)

		self.connect(self, self.pack, self.reunpack, self.mapper, self.rrc_filter, self)
Esempio n. 12
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    def __init__(self, fg, spb, alpha, gain, use_barker=0):
        if not isinstance(spb, int) or spb < 2:
            raise TypeError, "sbp must be an integer >= 2"
        self.spb = spb
        self.bits_per_chunk = 1

	ntaps = 2 * spb - 1
        alpha = 0.5

        self.bytes2chunks = gr.packed_to_unpacked_bb(self.bits_per_chunk,
                                                     gr.GR_MSB_FIRST)

        constellation = ( (), ( -1-0j,1+0j ), ( 0.707+0.707j,-0.707-0.707j ),
                          ( 0.707+0j,-0.707-0.707j ), ( -1+0j,-1j, 1j, 1+0j ),
                          ( 1+0j,0+1j,-1+0j,0-1j ), ( 0+0j,1+0j ) )

        self.chunks2symbols = gr.chunks_to_symbols_bc(constellation[2])
        self.scrambler = bbn.scrambler_bb(True)
        self.diff_encode = gr.diff_encoder_bb(2);

        self.barker_taps = bbn.firdes_barker(spb)

	self.rrc_taps = gr.firdes.root_raised_cosine(4 * gain, spb,
		1.0, alpha, ntaps)

        if use_barker:
            self.tx_filter = gr.interp_fir_filter_ccf(spb, self.barker_taps)
        else:
            self.tx_filter = gr.interp_fir_filter_ccf(spb, self.rrc_taps)

        fg.connect(self.scrambler, self.bytes2chunks)
        fg.connect(self.bytes2chunks, self.diff_encode)
        fg.connect(self.diff_encode, self.chunks2symbols)
	fg.connect(self.chunks2symbols,self.tx_filter)

        gr.hier_block.__init__(self, fg, self.scrambler, self.tx_filter)
        bbn.crc16_init()
Esempio n. 13
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 def __init__(self, sps, excess_bw, amplitude, vector_source): 
     try:
         self.sps = 2
     except KeyError:
         pass
     
     gr.hier_block2.__init__(self, "OQPSK Modulator",
                             gr.io_signature(0, 0, 0),                     # Input 
                             gr.io_signature(1, 1, gr.sizeof_gr_complex))  # Output 
     
     if not isinstance(self.sps, int) or self.sps < 2: 
         raise TypeError, "sample per symbol  sps ou spb must be an integer >= 2"
     
     self.vector_source = vector_source
     
     self.symbolsToChips = ucla.symbols_to_chips_bi()
     
     self.chipsToSymbols = gr.packed_to_unpacked_ii(2, gr.GR_MSB_FIRST)
     
     #self.symbolsToConstellation = gr.chunks_to_symbols_ic((-1-1j, -1+1j, 1-1j, 1+1j))
     self.symbolsToConstellation = gr.chunks_to_symbols_bc((-1-1j, -1+1j, 1-1j, 1+1j))
     
     #self._scrambler = gr.scrambler_bb(0x8A, 0x7F, 31) # CCSDS 7-bit scrambler
     
     self.pskmod = ucla.qpsk_modulator_cc()
     
     self.delay = ucla.delay_cc(self.sps)
     
     self.amp = gr.multiply_const_cc(amplitude) 
     
     #self.connect(self.vector_source , self.symbolsToChips, self.chipsToSymbols, self.symbolsToConstellation, self.pskmod, self.delay, self.amp, self)
     
     #self.connect(self.vector_source , self._scrambler, self.symbolsToConstellation, self.pskmod, self.delay, self.amp, self)
     self.connect(self.vector_source, self.symbolsToConstellation, self.pskmod, self.delay, self.amp, self)
 
     #self.connect(self, self.symbolsToChips, self.chipsToSymbols, self.symbolsToConstellation, self.pskmod, self)
Esempio n. 14
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    def __init__(self,
                 samples_per_symbol=_def_samples_per_symbol,
                 excess_bw=_def_excess_bw,
                 gray_code=_def_gray_code,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered differential BPSK modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.
        
	@param samples_per_symbol: samples per baud >= 2
	@type samples_per_symbol: integer
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_code: Tell modulator to Gray code the bits
        @type gray_code: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param log: Log modulation data to files?
        @type log: bool
	"""

	gr.hier_block2.__init__(self, "dbpsk_mod",
				gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
				gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature

        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._gray_code = gray_code

        if self._samples_per_symbol < 2:
            raise TypeError, ("sbp must be an integer >= 2, is %d" % self._samples_per_symbol)
        
        arity = pow(2,self.bits_per_symbol())
        
        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            self.symbol_mapper = gr.map_bb(psk.binary_to_gray[arity])
        else:
            self.symbol_mapper = gr.map_bb(psk.binary_to_ungray[arity])

        self.diffenc = gr.diff_encoder_bb(arity)

        self.chunks2symbols = gr.chunks_to_symbols_bc(psk.constellation[arity])

        # pulse shaping filter
        nfilts = 32
        ntaps = nfilts * 11 * int(self._samples_per_symbol)    # make nfilts filters of ntaps each
        self.rrc_taps = gr.firdes.root_raised_cosine(
            nfilts,          # gain
            nfilts,          # sampling rate based on 32 filters in resampler
            1.0,             # symbol rate
            self._excess_bw, # excess bandwidth (roll-off factor)
            ntaps)
        self.rrc_filter = gr.pfb_arb_resampler_ccf(self._samples_per_symbol, self.rrc_taps)

	# Connect
        self.connect(self, self.bytes2chunks, self.symbol_mapper, self.diffenc,
                     self.chunks2symbols, self.rrc_filter, self)

        if verbose:
            self._print_verbage()
            
        if log:
            self._setup_logging()
    def __init__(self, constellation,
                 samples_per_symbol=_def_samples_per_symbol,
                 differential=_def_differential,
                 excess_bw=_def_excess_bw,
                 gray_coded=True,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered differential generic modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.
        
	@param constellation: determines the modulation type
	@type constellation: gnuradio.digital.gr_constellation
	@param samples_per_symbol: samples per baud >= 2
	@type samples_per_symbol: float
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_coded: turn gray coding on/off
        @type gray_coded: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param log: Log modulation data to files?
        @type log: bool
	"""

	gr.hier_block2.__init__(self, "generic_mod",
				gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
				gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature

        self._constellation = constellation.base()
        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._differential = differential

        if self._samples_per_symbol < 2:
            raise TypeError, ("sbp must be >= 2, is %f" % self._samples_per_symbol)
        
        arity = pow(2,self.bits_per_symbol())
        
        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if gray_coded == True:
            self.symbol_mapper = gr.map_bb(self._constellation.pre_diff_code())

        if differential:
            self.diffenc = gr.diff_encoder_bb(arity)

        self.chunks2symbols = gr.chunks_to_symbols_bc(self._constellation.points())

        # pulse shaping filter
        nfilts = 32
        ntaps = nfilts * 11 * int(self._samples_per_symbol)    # make nfilts filters of ntaps each
        self.rrc_taps = gr.firdes.root_raised_cosine(
            nfilts,          # gain
            nfilts,          # sampling rate based on 32 filters in resampler
            1.0,             # symbol rate
            self._excess_bw, # excess bandwidth (roll-off factor)
            ntaps)
        self.rrc_filter = gr.pfb_arb_resampler_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

	# Connect
        blocks = [self, self.bytes2chunks]
        if gray_coded == True:
            blocks.append(self.symbol_mapper)
        if differential:
            blocks.append(self.diffenc)
        blocks += [self.chunks2symbols, self.rrc_filter, self]
        self.connect(*blocks)

        if verbose:
            self._print_verbage()
            
        if log:
            self._setup_logging()
Esempio n. 16
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    def __init__(self,
                 samples_per_symbol=_def_samples_per_symbol,
                 excess_bw=_def_excess_bw,
                 gray_code=_def_gray_code,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered QPSK modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.

	@param samples_per_symbol: samples per symbol >= 2
	@type samples_per_symbol: integer
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_code: Tell modulator to Gray code the bits
        @type gray_code: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param debug: Print modualtion data to files?
        @type debug: bool
	"""

        gr.hier_block2.__init__(
            self,
            "qam8_mod",
            gr.io_signature(1, 1, gr.sizeof_char),  # Input signature
            gr.io_signature(1, 1, gr.sizeof_gr_complex))  # Output signature

        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._gray_code = gray_code

        if not isinstance(samples_per_symbol, int) or samples_per_symbol < 2:
            raise TypeError, ("sbp must be an integer >= 2, is %d" %
                              samples_per_symbol)

        ntaps = 11 * samples_per_symbol

        arity = pow(2, self.bits_per_symbol())

        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            self.symbol_mapper = gr.map_bb(qam.binary_to_gray[arity])
        else:
            self.symbol_mapper = gr.map_bb(qam.binary_to_ungray[arity])

        self.diffenc = gr.diff_encoder_bb(arity)

        rot = 1.0
        print "constellation with %d arity" % arity
        rotated_const = map(lambda pt: pt * rot, qam.constellation[arity])
        self.chunks2symbols = gr.chunks_to_symbols_bc(rotated_const)

        # pulse shaping filter
        self.rrc_taps = gr.firdes.root_raised_cosine(
            self.
            _samples_per_symbol,  # gain  (sps since we're interpolating by sps)
            self._samples_per_symbol,  # sampling rate
            1.0,  # symbol rate
            self._excess_bw,  # excess bandwidth (roll-off factor)
            ntaps)

        self.rrc_filter = gr.interp_fir_filter_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

        if verbose:
            self._print_verbage()

        if log:
            self._setup_logging()

# Connect
        self.connect(self, self.bytes2chunks, self.symbol_mapper, self.diffenc,
                     self.chunks2symbols, self.rrc_filter, self)
Esempio n. 17
0
    def __init__(self,
                 samples_per_symbol=_def_samples_per_symbol,
                 excess_bw=_def_excess_bw,
                 gray_code=_def_gray_code,
                 verbose=_def_verbose,
                 log=_def_log):

        """
	Hierarchical block for RRC-filtered QPSK modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.

	@param samples_per_symbol: samples per symbol >= 2
	@type samples_per_symbol: integer
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_code: Tell modulator to Gray code the bits
        @type gray_code: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param debug: Print modualtion data to files?
        @type debug: bool
	"""

	gr.hier_block2.__init__(self, "qam8_mod",
				gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
				gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature

        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._gray_code = gray_code

        if not isinstance(samples_per_symbol, int) or samples_per_symbol < 2:
            raise TypeError, ("sbp must be an integer >= 2, is %d" % samples_per_symbol)

	ntaps = 11 * samples_per_symbol
 
        arity = pow(2, self.bits_per_symbol())

        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            self.symbol_mapper = gr.map_bb(qam.binary_to_gray[arity])
        else:
            self.symbol_mapper = gr.map_bb(qam.binary_to_ungray[arity])
            
        self.diffenc = gr.diff_encoder_bb(arity)

        rot = 1.0
        print "constellation with %d arity" % arity
        rotated_const = map(lambda pt: pt * rot, qam.constellation[arity])
        self.chunks2symbols = gr.chunks_to_symbols_bc(rotated_const)

        # pulse shaping filter
	self.rrc_taps = gr.firdes.root_raised_cosine(
	    self._samples_per_symbol, # gain  (sps since we're interpolating by sps)
            self._samples_per_symbol, # sampling rate
            1.0,		      # symbol rate
            self._excess_bw,          # excess bandwidth (roll-off factor)
            ntaps)

	self.rrc_filter = gr.interp_fir_filter_ccf(self._samples_per_symbol, self.rrc_taps)

        if verbose:
            self._print_verbage()
        
        if log:
            self._setup_logging()
            
	# Connect
        self.connect(self, self.bytes2chunks, self.symbol_mapper, self.diffenc,
                     self.chunks2symbols, self.rrc_filter, self)
Esempio n. 18
0
    def __init__(self,
                 constellation,
                 samples_per_symbol=_def_samples_per_symbol,
                 differential=_def_differential,
                 excess_bw=_def_excess_bw,
                 gray_coded=True,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered differential generic modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.
        
	@param constellation: determines the modulation type
	@type constellation: gnuradio.digital.gr_constellation
	@param samples_per_symbol: samples per baud >= 2
	@type samples_per_symbol: float
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_coded: turn gray coding on/off
        @type gray_coded: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param log: Log modulation data to files?
        @type log: bool
	"""

        gr.hier_block2.__init__(
            self,
            "generic_mod",
            gr.io_signature(1, 1, gr.sizeof_char),  # Input signature
            gr.io_signature(1, 1, gr.sizeof_gr_complex))  # Output signature

        self._constellation = constellation.base()
        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._differential = differential

        if self._samples_per_symbol < 2:
            raise TypeError, ("sbp must be >= 2, is %f" %
                              self._samples_per_symbol)

        arity = pow(2, self.bits_per_symbol())

        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if gray_coded == True:
            self.symbol_mapper = gr.map_bb(self._constellation.pre_diff_code())

        if differential:
            self.diffenc = gr.diff_encoder_bb(arity)

        self.chunks2symbols = gr.chunks_to_symbols_bc(
            self._constellation.points())

        # pulse shaping filter
        nfilts = 32
        ntaps = nfilts * 11 * int(
            self._samples_per_symbol)  # make nfilts filters of ntaps each
        self.rrc_taps = gr.firdes.root_raised_cosine(
            nfilts,  # gain
            nfilts,  # sampling rate based on 32 filters in resampler
            1.0,  # symbol rate
            self._excess_bw,  # excess bandwidth (roll-off factor)
            ntaps)
        self.rrc_filter = gr.pfb_arb_resampler_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

        # Connect
        blocks = [self, self.bytes2chunks]
        if gray_coded == True:
            blocks.append(self.symbol_mapper)
        if differential:
            blocks.append(self.diffenc)
        blocks += [self.chunks2symbols, self.rrc_filter, self]
        self.connect(*blocks)

        if verbose:
            self._print_verbage()

        if log:
            self._setup_logging()
    def __init__(self, gui, options):
        gr.hier_block2.__init__(self, "bpsk_mod",
                                gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
                                gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
        
        self._samples_per_symbol = options.sps
        self.amplitude = options.amplitude
        self.verbose = options.verbose
        
        self._excess_bw = _def_excess_bw
        self._gray_code = _def_gray_code

        if not isinstance(self._samples_per_symbol, int) or self._samples_per_symbol < 2:
            raise TypeError, ("sample per symbol must be an integer >= 2, is %d" % self._samples_per_symbol)
    

        arity = pow(2,self.bits_per_symbol())
        
        # turn bytes into k-bit vectors
        self.packed_to_unpacked_bb = \
            gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            self.symbol_mapper = gr.map_bb(psk.binary_to_gray[arity])
        else:
            self.symbol_mapper = gr.map_bb(psk.binary_to_ungray[arity])
        self.diff_encoder_bb = gr.diff_encoder_bb(arity)
            
        #This bloc allow to decode the stream
        #self.scrambler = gr.scrambler_bb(0x8A, 0x7F, 7)
        
        #Transform symbols to chips
        self.symbols_to_chips = ieee.symbols_to_chips_bs()

        #self.chunks2symbols = gr.chunks_to_symbols_ic(psk.constellation[arity])
        self.chunks2symbols = gr.chunks_to_symbols_sc([-1+0j, 1+0j])
        self.chunks2symbols_b = gr.chunks_to_symbols_bc([-1+0j, 1+0j])
        
        # transform chips to symbols
        print "bits_per_symbol", self.bits_per_symbol()
        self.packed_to_unpacked_ss = \
          gr.packed_to_unpacked_ss(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        ntaps = 11 * self._samples_per_symbol
        # pulse shaping filter
        self.rrc_taps = gr.firdes.root_raised_cosine(
                                                     self._samples_per_symbol * self.amplitude,   # gain (samples_per_symbol since we're
                                                                                # interpolating by samples_per_symbol)
                                                     self._samples_per_symbol,   # sampling rate
                                                     1.0,                # symbol rate
                                                     self._excess_bw,            # excess bandwidth (roll-off factor)
                                                     ntaps)
        self.rrc_filter = gr.interp_fir_filter_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

        # Connect
        #self.connect(self, self.bytes2chunks, self.symbol_mapper,self.scrambler, self.chunks2symbols, self.rrc_filter, self)
        
#        self.wxgui_constellationsink2_0 = constsink_gl.const_sink_c(
#            gui.GetWin(),
#            title="Constellation Plot",
#            sample_rate=self._samples_per_symbol,
#            frame_rate=5,
#            const_size=2048,
#            M=2,
#            theta=0,
#            alpha=0.005,
#            fmax=0.06,
#            mu=0.5,
#            gain_mu=0.005,
#            symbol_rate=self._samples_per_symbol/2,
#            omega_limit=0.005,
#        )
#        gui.Add(self.wxgui_constellationsink2_0.win)
        
        #Modefied for IEEE 802.15.4
        #self.connect(self, self.packed_to_unpacked_bb, self.symbol_mapper, self.diff_encoder_bb, self.symbols_to_chips, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        
        self.connect(self, self.packed_to_unpacked_bb, self.symbol_mapper, self.symbols_to_chips, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        #self.connect(self, self.symbols_to_chips, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        
        #self.connect(self, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)

        #self.connect(self, self._scrambler, self.chunks2symbols_b, self.rrc_filter, self)
        
        #self.connect(self.rrc_filter, self.wxgui_constellationsink2_0)


        if self.verbose:
            self._print_verbage()
Esempio n. 20
0
    def __init__(self,
                 samples_per_symbol=_def_samples_per_symbol,
                 excess_bw=_def_excess_bw,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered QPSK modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.

	@param samples_per_symbol: samples per symbol >= 2
	@type samples_per_symbol: integer
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param debug: Print modualtion data to files?
        @type debug: bool
	"""

	gr.hier_block2.__init__(self, "cqpsk_mod",
				gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
				gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature

        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw

        if not isinstance(samples_per_symbol, int) or samples_per_symbol < 2:
            raise TypeError, ("sbp must be an integer >= 2, is %d" % samples_per_symbol)

	ntaps = 11 * samples_per_symbol
 
        arity = 8

        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        #	0	+45	1	[+1]
        #	1	+135	3	[+3]
        #	2	-45	7	[-1]
        #	3	-135	5	[-3]
        self.pi4map = [1, 3, 7, 5]
        self.symbol_mapper = gr.map_bb(self.pi4map)
        self.diffenc = gr.diff_encoder_bb(arity)
        self.chunks2symbols = gr.chunks_to_symbols_bc(psk.constellation[arity])

        # pulse shaping filter
	self.rrc_taps = firdes.root_raised_cosine(
	    self._samples_per_symbol, # gain  (sps since we're interpolating by sps)
            self._samples_per_symbol, # sampling rate
            1.0,		      # symbol rate
            self._excess_bw,          # excess bandwidth (roll-off factor)
            ntaps)

	self.rrc_filter = filter.interp_fir_filter_ccf(self._samples_per_symbol, self.rrc_taps)

        if verbose:
            self._print_verbage()
        
        if log:
            self._setup_logging()
            
	# Connect & Initialize base class
        self.connect(self, self.bytes2chunks, self.symbol_mapper, self.diffenc,
                     self.chunks2symbols, self.rrc_filter, self)
Esempio n. 21
0
    def __init__(self, fg, spb, alpha, gain, use_barker=0):
        """
	Hierarchical block for RRC-filtered PSK modulation
	modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.

	@param fg: flow graph
	@type fg: flow graph
	@param spb: samples per baud >= 2
	@type spb: integer
	@param alpha: Root-raised cosine filter excess bandwidth
	@type alpha: float
	"""
        if not isinstance(spb, int) or spb < 2:
            raise TypeError, "sbp must be an integer >= 2"
        self.spb = spb
        self.bits_per_chunk = 1

	ntaps = 2 * spb - 1
        alpha = 0.5

        # turn bytes into symbols
        self.bytes2chunks = gr.packed_to_unpacked_bb(self.bits_per_chunk,
                                                     gr.GR_MSB_FIRST)

        constellation = ( (),
                          ( -1-0j,1+0j ),
                          ( 0.707+0.707j,-0.707-0.707j ),
                          ( 0.707+0j,-0.707-0.707j ),
                          ( -1+0j,-1j, 1j, 1+0j),
                          ( 1+0j,0+1j,-1+0j,0-1j ),
                          ( 0+0j,1+0j ),
                          )

        self.chunks2symbols = gr.chunks_to_symbols_bc(constellation[2])
        self.scrambler = bbn.scrambler_bb(True)
        self.diff_encode = gr.diff_encoder_bb(2);

        self.barker_taps = bbn.firdes_barker(spb)

	# Form Raised Cosine filter
	self.rrc_taps = gr.firdes.root_raised_cosine(
		4 * gain,     	# gain  FIXME may need to be spb
		spb,            # sampling freq
		1.0,		# symbol_rate
		alpha,
                ntaps)

        if use_barker:
            self.tx_filter = gr.interp_fir_filter_ccf(spb, self.barker_taps)
        else:
            self.tx_filter = gr.interp_fir_filter_ccf(spb, self.rrc_taps)

	# Connect
        fg.connect(self.scrambler, self.bytes2chunks)
        fg.connect(self.bytes2chunks, self.diff_encode)
        fg.connect(self.diff_encode, self.chunks2symbols)
	fg.connect(self.chunks2symbols,self.tx_filter)

	# Initialize base class
        gr.hier_block.__init__(self, fg, self.scrambler, self.tx_filter)
        bbn.crc16_init()
    def __init__(self, principal_gui, options):
        gr.hier_block2.__init__(self, "bpsk_mod",
                                gr.io_signature(1, 1, gr.sizeof_char),       # Input signature
                                gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
        
        self._samples_per_symbol = options.sps
        self.amplitude = options.amplitude
        self.verbose = options.verbose
        
        self._excess_bw = _def_excess_bw
        self._gray_code = _def_gray_code

        if not isinstance(self._samples_per_symbol, int) or self._samples_per_symbol < 2:
            raise TypeError, ("sample per symbol must be an integer >= 2, is %d" % self._samples_per_symbol)
    

        arity = pow(2,self.bits_per_symbol())
        
        #arity = pow (2, 2)
        # turn bytes into k-bit vectors
        self.packed_to_unpacked_bb = \
            gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            map_param = psk.binary_to_gray[arity]
            self.symbol_mapper = gr.map_bb(map_param)
        else:
            self.symbol_mapper = gr.map_bb(psk.binary_to_ungray[arity])
        self.diff_encoder_bb = gr.diff_encoder_bb(arity)
            
        #This bloc allow to decode the stream
        #self.scrambler = gr.scrambler_bb(0x8A, 0x7F, 7)
        
        #Transform symbols to chips
        self.symbols_to_chips = ieee.symbols_to_chips_bs()

        #self.chunks2symbols = gr.chunks_to_symbols_ic(psk.constellation[arity])
        self.chunks2symbols = gr.chunks_to_symbols_sc([-1+0j, 1+0j])
        self.chunks2symbols_b = gr.chunks_to_symbols_bc([-1+0j, 1+0j])
        
        # transform chips to symbols
        print "bits_per_symbol", self.bits_per_symbol()
        self.packed_to_unpacked_ss = \
          gr.packed_to_unpacked_ss(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        ntaps = 11 * self._samples_per_symbol
        # pulse shaping filter
        self.rrc_taps = gr.firdes.root_raised_cosine(
                                                     self._samples_per_symbol,   # gain (samples_per_symbol since we're
                                                                                 # interpolating by samples_per_symbol)
                                                     self._samples_per_symbol,   # sampling rate
                                                     1.0,                # symbol rate
                                                     self._excess_bw,            # excess bandwidth (roll-off factor)
                                                     ntaps)
        self.rrc_filter = gr.interp_fir_filter_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

        # Connect
        #self.connect(self, self.bytes2chunks, self.symbol_mapper,self.scrambler, self.chunks2symbols, self.rrc_filter, self)
   
        #Modefied for IEEE 802.15.4
        #self.connect(self, self.packed_to_unpacked_bb, self.symbol_mapper, self.diff_encoder_bb, self.symbols_to_chips, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        
        #For IEEE 802.15.4 915 868 MHz standard 
        self.connect(self, self.packed_to_unpacked_bb, self.symbol_mapper, self.symbols_to_chips, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        
        
        #self.connect(self, self.symbols_to_chips, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        #self.connect(self, self.packed_to_unpacked_ss,  self.chunks2symbols, self.rrc_filter, self)
        
        #case when we use a stream of bits
        #self.connect(self, self.chunks2symbols_b, self.rrc_filter, self)


        if self.verbose:
            self._print_verbage()
Esempio n. 23
0
    def __init__(self,
                 samples_per_symbol=_def_samples_per_symbol,
                 excess_bw=_def_excess_bw,
                 gray_code=_def_gray_code,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered QPSK modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.

	@param samples_per_symbol: samples per symbol >= 2
	@type samples_per_symbol: integer
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_code: Tell modulator to Gray code the bits
        @type gray_code: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param debug: Print modualtion data to files?
        @type debug: bool
	"""

        gr.hier_block2.__init__(
            self,
            "dqpsk2_mod",
            gr.io_signature(1, 1, gr.sizeof_char),  # Input signature
            gr.io_signature(1, 1, gr.sizeof_gr_complex))  # Output signature

        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._gray_code = gray_code

        if samples_per_symbol < 2:
            raise TypeError, ("sbp must be >= 2, is %f" % samples_per_symbol)

        ntaps = 11 * samples_per_symbol

        arity = pow(2, self.bits_per_symbol())

        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            self.symbol_mapper = gr.map_bb(psk.binary_to_gray[arity])
        else:
            self.symbol_mapper = gr.map_bb(psk.binary_to_ungray[arity])

        self.diffenc = gr.diff_encoder_bb(arity)

        rot = .707 + .707j
        rotated_const = map(lambda pt: pt * rot, psk.constellation[arity])
        self.chunks2symbols = gr.chunks_to_symbols_bc(rotated_const)

        # pulse shaping filter
        nfilts = 32
        ntaps = 11 * int(
            nfilts *
            self._samples_per_symbol)  # make nfilts filters of ntaps each
        self.rrc_taps = gr.firdes.root_raised_cosine(
            nfilts,  # gain
            nfilts,  # sampling rate based on 32 filters in resampler
            1.0,  # symbol rate
            self._excess_bw,  # excess bandwidth (roll-off factor)
            ntaps)
        self.rrc_filter = gr.pfb_arb_resampler_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

        if verbose:
            self._print_verbage()

        if log:
            self._setup_logging()

# Connect & Initialize base class
        self.connect(self, self.bytes2chunks, self.symbol_mapper, self.diffenc,
                     self.chunks2symbols, self.rrc_filter, self)
    def __init__(self, fg,
                 samples_per_symbol=_def_samples_per_symbol,
                 excess_bw=_def_excess_bw,
                 gray_code=_def_gray_code,
                 verbose=_def_verbose,
                 log=_def_log):
        """
	Hierarchical block for RRC-filtered differential BPSK modulation.

	The input is a byte stream (unsigned char) and the
	output is the complex modulated signal at baseband.
        
	@param fg: flow graph
	@type fg: flow graph
	@param samples_per_symbol: samples per baud >= 2
	@type samples_per_symbol: integer
	@param excess_bw: Root-raised cosine filter excess bandwidth
	@type excess_bw: float
        @param gray_code: Tell modulator to Gray code the bits
        @type gray_code: bool
        @param verbose: Print information about modulator?
        @type verbose: bool
        @param log: Log modulation data to files?
        @type log: bool
	"""

        self._fg = fg
        self._samples_per_symbol = samples_per_symbol
        self._excess_bw = excess_bw
        self._gray_code = gray_code

        if not isinstance(self._samples_per_symbol, int) or self._samples_per_symbol < 2:
            raise TypeError, ("sbp must be an integer >= 2, is %d" % self._samples_per_symbol)
        
	ntaps = 11 * self._samples_per_symbol

        arity = pow(2,self.bits_per_symbol())
        
        # turn bytes into k-bit vectors
        self.bytes2chunks = \
          gr.packed_to_unpacked_bb(self.bits_per_symbol(), gr.GR_MSB_FIRST)

        if self._gray_code:
            self.symbol_mapper = gr.map_bb(psk.binary_to_gray[arity])
        else:
            self.symbol_mapper = gr.map_bb(psk.binary_to_ungray[arity])

        self.diffenc = gr.diff_encoder_bb(arity)

        self.chunks2symbols = gr.chunks_to_symbols_bc(psk.constellation[arity])

        # pulse shaping filter
	self.rrc_taps = gr.firdes.root_raised_cosine(
	    self._samples_per_symbol,   # gain (samples_per_symbol since we're
                                        # interpolating by samples_per_symbol)
	    self._samples_per_symbol,   # sampling rate
	    1.0,		        # symbol rate
	    self._excess_bw,            # excess bandwidth (roll-off factor)
            ntaps)
	self.rrc_filter = gr.interp_fir_filter_ccf(self._samples_per_symbol,
                                                   self.rrc_taps)

	# Connect
        fg.connect(self.bytes2chunks, self.symbol_mapper, self.diffenc,
                   self.chunks2symbols, self.rrc_filter)

        if verbose:
            self._print_verbage()
            
        if log:
            self._setup_logging()
            
	# Initialize base class
	gr.hier_block.__init__(self, self._fg, self.bytes2chunks, self.rrc_filter)