def __init__(self):
gr.hier_block2.__init__(self, "ofdm_tx",
gr.io_signature(1, 1, gr.sizeof_char),
gr.io_signature(1, 1, gr.sizeof_gr_complex))
self.sequencr = aux.insert_sequence_numbers_bb()
self.encoder = aux.encoder_reed_solomon_bb()
self.framer = blocks.stream_to_tagged_stream(
gr.sizeof_char, 1, config.get_bytes_per_frame(),
LEN_TAG_KEY) #divide the incoming data streams in frames
self.connect(self, self.sequencr, self.encoder, self.framer)
#We can do some byte scrambling if needed (variable modulus modulation )
self.unpacker_data_stream = blocks.repack_bits_bb( #modulation of the data (split the bytes, and modulate the split bytes
8, config.get_bits_per_symbol(), LEN_TAG_KEY)
self.modulator_data_stream = digital.chunks_to_symbols_bc(
config.get_constellation().points())
self.connect(self.framer, self.unpacker_data_stream,
self.modulator_data_stream)
self.allocator = digital.ofdm_carrier_allocator_cvc(
config.get_fft_length(),
occupied_carriers=config.get_data_tones(),
pilot_carriers=config.get_pilot_tones(),
pilot_symbols=config.get_pilot_symbols(),
sync_words=config.get_preambles(),
len_tag_key=LEN_TAG_KEY)
self.connect(self.modulator_data_stream, self.allocator)
self.fft_block = fft.fft_vcc(config.get_fft_length(), False, (), True)
self.connect(self.allocator, self.fft_block)
self.prefixer = digital.ofdm_cyclic_prefixer(
config.get_fft_length(),
config.get_cp_length() + config.get_fft_length(), 0, LEN_TAG_KEY)
self.burst_handler = aux.add_zeros_cc(
14, 104) #digital.burst_shaper_cc([],1040,1040,False, LEN_TAG_KEY)
self.connect(self.fft_block, self.prefixer, self.burst_handler)
self.connect(self.burst_handler, self)
def __init__(self):
gr.hier_block2.__init__(self, "ofdm_rx",
gr.io_signature(1, 1, gr.sizeof_gr_complex),
gr.io_signature(1, 1, gr.sizeof_char))
self.detector = digital.ofdm_sync_sc_cfb(config.get_fft_length(), config.get_cp_length(), False, 0.95)
self.connect(self,self.detector)
self.mixer = blocks.multiply_cc()
self.delay_block = blocks.delay(gr.sizeof_gr_complex, config.get_fft_length() + config.get_cp_length() + SAFETY) #delay one ofdm symbol to get both preambles for channel estimation
self.oscillator = analog.frequency_modulator_fc(-2.0 / config.get_fft_length())
self.connect(self,self.delay_block)
self.connect((self.detector,0), self.oscillator)
self.connect(self.delay_block, (self.mixer,0))
self.connect(self.oscillator, (self.mixer,1))
self.frame_filter = aux.filter_frame_cvc(config.get_frame_length(), config.get_fft_length(), config.get_cp_length())
#self.connect(self.frame_filter,blocks.file_sink(gr.sizeof_gr_complex*config.get_fft_length(),"result.dat"))
self.connect(self.mixer, (self.frame_filter,0))
self.connect((self.detector,1), (self.frame_filter,1))
self.framer = blocks.stream_to_tagged_stream(gr.sizeof_gr_complex, config.get_fft_length(), config.get_frame_length() , LEN_TAG_KEY)
self.fft_block = fft.fft_vcc(config.get_fft_length(), True, (), True)
self.connect(self.frame_filter,self.fft_block)
self.chanest = digital.ofdm_chanest_vcvc(config.get_sync_word_one(),config.get_sync_word_two(), config.get_number_of_data_symbols())
self.connect((self.fft_block), self.chanest)
self.equalizer = digital.ofdm_equalizer_simpledfe(
config.get_fft_length(),
config.get_constellation().base(),
config.get_data_tones(),
config.get_pilot_tones(),
config.get_pilot_symbols(),
symbols_skipped=0,
)
self.equalizer_block = digital.ofdm_frame_equalizer_vcvc(
self.equalizer.base(),
config.get_cp_length(),
LEN_TAG_KEY,
True,
config.get_number_of_data_symbols() # Header is 1 symbol long
)
self.connect(self.chanest, self.equalizer_block)
self.serializer = digital.ofdm_serializer_vcc(
config.get_fft_length(), config.get_data_tones(),
LEN_TAG_KEY
)
self.connect(self.equalizer_block, self.serializer)
self.demod = digital.constellation_decoder_cb(config.get_constellation().base())
self.repack = blocks.repack_bits_bb(config.get_bits_per_symbol(), 8, LEN_TAG_KEY, True)
self.connect( self.serializer, self.demod, self.repack)
self.decoder = aux.decoder_reed_solomon_bb()
self.commit_unt = aux.commit_to_output_bb()
self.connect(self.repack, (self.decoder,0), (self.commit_unt,0), self)
self.connect((self.decoder,1), (self.commit_unt,1))