#!/usr/bin/env python # # Copyright 2008 Free Software Foundation, Inc. # # This file is part of GNU Radio # # GNU Radio is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 3, or (at your option) # any later version. # # GNU Radio is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with GNU Radio; see the file COPYING. If not, write to # the Free Software Foundation, Inc., 51 Franklin Street, # Boston, MA 02110-1301, USA. # # Andreas Mueller, 2008 # andrmuel@ee.ethz.ch from gnuradio import gr, trellis, blocks, digital from . import dab_python as grdab from math import sqrt """ DAB FIC layer """ class fic_decode(gr.hier_block2): """ @brief block to decode FIBs (fast information blocks) from the FIC (fast information channel) of a demodulated DAB signal - get FIBs from byte stream - do convolutional decoding - undo energy dispersal - get FIC information """ def __init__(self, dab_params, verbose=False, debug=False): """ Hierarchical block for FIC decoding @param dab_params DAB parameter object (grdab.parameters.dab_parameters) """ gr.hier_block2.__init__(self, "fic", gr.io_signature(1, 1, gr.sizeof_float * dab_params.num_carriers * 2), gr.io_signature(1, 1, gr.sizeof_char * 32)) self.dp = dab_params self.verbose = verbose self.debug = debug # FIB selection and block partitioning self.select_fic_syms = grdab.select_vectors(gr.sizeof_float, self.dp.num_carriers * 2, self.dp.num_fic_syms, 0) self.repartition_fic = grdab.repartition_vectors(gr.sizeof_float, self.dp.num_carriers * 2, self.dp.fic_punctured_codeword_length, self.dp.num_fic_syms, self.dp.num_cifs) # unpuncturing self.unpuncture = grdab.unpuncture_vff(self.dp.assembled_fic_puncturing_sequence, 0) # convolutional coding # self.fsm = trellis.fsm(self.dp.conv_code_in_bits, self.dp.conv_code_out_bits, self.dp.conv_code_generator_polynomials) self.fsm = trellis.fsm(1, 4, [0o133, 0o171, 0o145, 0o133]) # OK (dumped to text and verified partially) self.conv_v2s = blocks.vector_to_stream(gr.sizeof_float, self.dp.fic_conv_codeword_length) # self.conv_decode = trellis.viterbi_combined_fb(self.fsm, 20, 0, 0, 1, [1./sqrt(2),-1/sqrt(2)] , trellis.TRELLIS_EUCLIDEAN) table = [ 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1 ] assert (len(table) / 4 == self.fsm.O()) table = [(1 - 2 * x) / sqrt(2) for x in table] self.conv_decode = trellis.viterbi_combined_fb(self.fsm, 774, 0, 0, 4, table, digital.TRELLIS_EUCLIDEAN) #self.conv_s2v = blocks.stream_to_vector(gr.sizeof_char, 774) self.conv_prune = grdab.prune(gr.sizeof_char, self.dp.fic_conv_codeword_length // 4, 0, self.dp.conv_code_add_bits_input) # energy dispersal self.prbs_src = blocks.vector_source_b(self.dp.prbs(self.dp.energy_dispersal_fic_vector_length), True) #self.energy_v2s = blocks.vector_to_stream(gr.sizeof_char, self.dp.energy_dispersal_fic_vector_length) self.add_mod_2 = blocks.xor_bb() self.energy_s2v = blocks.stream_to_vector(gr.sizeof_char, self.dp.energy_dispersal_fic_vector_length) self.cut_into_fibs = grdab.repartition_vectors(gr.sizeof_char, self.dp.energy_dispersal_fic_vector_length, self.dp.fib_bits, 1, self.dp.energy_dispersal_fic_fibs_per_vector) # connect all self.nullsink = blocks.null_sink(gr.sizeof_char) self.pack = blocks.unpacked_to_packed_bb(1, gr.GR_MSB_FIRST) self.fibout = blocks.stream_to_vector(1, 32) # self.filesink = gr.file_sink(gr.sizeof_char, "debug/fic.dat") self.fibsink = grdab.fib_sink_vb() # self.connect((self,0), (self.select_fic_syms,0), (self.repartition_fic,0), self.unpuncture, self.conv_v2s, self.conv_decode, self.conv_s2v, self.conv_prune, self.energy_v2s, self.add_mod_2, self.energy_s2v, (self.cut_into_fibs,0), gr.vector_to_stream(1,256), gr.unpacked_to_packed_bb(1,gr.GR_MSB_FIRST), self.filesink) self.connect((self, 0), (self.select_fic_syms, 0), (self.repartition_fic, 0), self.unpuncture, self.conv_v2s, self.conv_decode, #self.conv_s2v, self.conv_prune, #self.energy_v2s, self.add_mod_2, self.energy_s2v, (self.cut_into_fibs, 0), blocks.vector_to_stream(1, 256), self.pack, self.fibout, self.fibsink) self.connect(self.fibout, self) self.connect(self.prbs_src, (self.add_mod_2, 1)) if self.debug: self.connect((self, 0), blocks.file_sink(gr.sizeof_float * self.dp.num_carriers * 2, "debug/transmission_frame.dat")) self.connect((self, 1), blocks.file_sink(gr.sizeof_char, "debug/transmission_frame_trigger.dat")) self.connect(self.select_fic_syms, blocks.file_sink(gr.sizeof_float * self.dp.num_carriers * 2, "debug/fic_select_syms.dat")) self.connect(self.repartition_fic, blocks.file_sink(gr.sizeof_float * self.dp.fic_punctured_codeword_length, "debug/fic_repartitioned.dat")) self.connect(self.unpuncture, blocks.file_sink(gr.sizeof_float * self.dp.fic_conv_codeword_length, "debug/fic_unpunctured.dat")) self.connect(self.conv_decode, blocks.file_sink(gr.sizeof_char, "debug/fic_decoded.dat")) self.connect(self.conv_prune, blocks.file_sink(gr.sizeof_char, "debug/fic_decoded_pruned.dat")) #self.connect(self.conv_decode, blocks.file_sink(gr.sizeof_char * self.dp.energy_dispersal_fic_vector_length, "debug/fic_energy_dispersal_undone.dat")) self.connect(self.pack, blocks.file_sink(gr.sizeof_char, "debug/fic_energy_undone.dat")) def get_ensemble_info(self): return self.fibsink.get_ensemble_info() def get_service_info(self): return self.fibsink.get_service_info() def get_service_labels(self): return self.fibsink.get_service_labels() def get_subch_info(self): return self.fibsink.get_subch_info() def get_programme_type(self): return self.fibsink.get_programme_type() def get_crc_passed(self): return self.fibsink.get_crc_passed() def set_print_channel_info(self, val): self.fibsink.set_print_channel_info(val)