1 /* -*- c++ -*- */ 2 /* 3 * Copyright 2015 Free Software Foundation, Inc. 4 * 5 * This file is part of GNU Radio 6 * 7 * GNU Radio is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 3, or (at your option) 10 * any later version. 11 * 12 * GNU Radio is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with GNU Radio; see the file COPYING. If not, write to 19 * the Free Software Foundation, Inc., 51 Franklin Street, 20 * Boston, MA 02110-1301, USA. 21 */ 22 23 24 #ifndef INCLUDED_FEC_POLAR_ENCODER_SYSTEMATIC_H 25 #define INCLUDED_FEC_POLAR_ENCODER_SYSTEMATIC_H 26 27 #include <gnuradio/fec/api.h> 28 #include <gnuradio/fec/generic_encoder.h> 29 #include <gnuradio/fec/polar_common.h> 30 31 namespace gr { 32 namespace fec { 33 namespace code { 34 35 /*! 36 * \brief systematic POLAR encoder 37 * for basic details see 'polar_common' class. 38 * \ingroup error_coding_blk 39 * 40 * \details 41 * expects values with MSB first. It needs a full information word and encodes it in one 42 * pass. Output is a codeword of block_size. 43 * 44 * Systematic encoding indicates that the info bit values are present in the codeword. 45 * 'info_bit_positions' may be obtained by ordering all non frozen_bit_positions in 46 * increasing order. One may extract them at their positions after a bit reversal 47 * operation. encoder -> decoder chain would need additional bit-reversal after encoding + 48 * before decoding. This is unnecessary. 49 */ 50 class FEC_API polar_encoder_systematic : public generic_encoder, public polar_common 51 { 52 public: 53 /*! 54 * Factory for a polar code encoder object. 55 * 56 * \param block_size defines the codeword size. It MUST be a 57 * power of 2. 58 * \param num_info_bits represents the number of information 59 * bits in a block. Also called frame_size. 60 * \param frozen_bit_positions is an integer vector which 61 * defines the position of all frozen bits in a block. 62 * Its size MUST be equal to block_size - num_info_bits. 63 * Also it must be sorted and every position must only 64 * occur once. Frozen bit values will be set to ZERO! 65 */ 66 static generic_encoder::sptr 67 make(int block_size, int num_info_bits, std::vector<int> frozen_bit_positions); 68 69 // FECAPI 70 void generic_work(void* in_buffer, void* out_buffer); rate()71 double rate() { return (1.0 * get_input_size() / get_output_size()); }; get_input_size()72 int get_input_size() { return num_info_bits(); }; get_output_size()73 int get_output_size() { return block_size(); }; set_frame_size(unsigned int frame_size)74 bool set_frame_size(unsigned int frame_size) { return false; }; 75 76 ~polar_encoder_systematic(); 77 78 private: 79 polar_encoder_systematic(int block_size, 80 int num_info_bits, 81 std::vector<int> frozen_bit_positions); 82 83 void bit_reverse_and_reset_frozen_bits(unsigned char* outbuf, 84 const unsigned char* inbuf); 85 unsigned char* d_volk_syst_intermediate; 86 }; 87 88 } // namespace code 89 } // namespace fec 90 } // namespace gr 91 92 #endif /* INCLUDED_FEC_POLAR_ENCODER_SYSTEMATIC_H */ 93