GNU Radio Manual and C++ API Reference 3.7.14.0
The Free & Open Software Radio Ecosystem
polar_decoder_common.h
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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,
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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_DECODER_COMMON_H
25#define INCLUDED_FEC_POLAR_DECODER_COMMON_H
26
27#include <gnuradio/fec/api.h>
30
31namespace gr {
32namespace fec {
33namespace code {
34
35/*!
36 * \brief Class holds common methods and attributes for different
37 * decoder implementations
38 */
40{
41public:
42 /*!
43 *
44 * \param block_size codeword size. MUST be a power of 2.
45 * \param num_info_bits represents the number of information bits
46 * in a block. Also called frame_size. <= block_size
47 * \param frozen_bit_positions is an integer vector which defines
48 * the position of all frozen bits in a block. Its size
49 * MUST be equal to block_size - num_info_bits. Also it
50 * must be sorted and every position must only occur once.
51 * \param frozen_bit_values holds an unpacked byte for every
52 * frozen bit position. It defines if a frozen bit is
53 * fixed to '0' or '1'. Defaults to all ZERO.
54 */
55 polar_decoder_common(int block_size,
56 int num_info_bits,
57 std::vector<int> frozen_bit_positions,
58 std::vector<char> frozen_bit_values);
60
61 // FECAPI
62 double rate() { return (1.0 * get_output_size() / get_input_size()); };
63 int get_input_size() { return block_size(); };
64 int get_output_size() { return num_info_bits(); };
65 bool set_frame_size(unsigned int frame_size) { return false; };
66
67private:
68 static const float D_LLR_FACTOR;
69 unsigned int d_frozen_bit_counter;
70
71protected:
72 // calculate LLRs for stage
73 float llr_odd(const float la, const float lb) const;
74 float llr_even(const float la, const float lb, const unsigned char f) const;
75 unsigned char llr_bit_decision(const float llr) const
76 {
77 return (llr < 0.0f) ? 1 : 0;
78 };
79
80 // control retrieval of frozen bits.
81 const bool is_frozen_bit(const int u_num) const;
82 const unsigned char next_frozen_bit();
83
84 // preparation for decoding
85 void initialize_decoder(unsigned char* u, float* llrs, const float* input);
86
87 // basic algorithm methods
89 float* llrs, unsigned char* u, const int stage, const int u_num, const int row);
91 float* llrs, unsigned char* u, const int stage, const int u_num, const int row);
93 float* llrs, unsigned char* u, const int stage, const int u_num, const int row);
94 void even_u_values(unsigned char* u_even, const unsigned char* u, const int u_num);
95 void
96 odd_xor_even_values(unsigned char* u_xor, const unsigned char* u, const int u_num);
97 void extract_info_bits(unsigned char* output, const unsigned char* input) const;
98
99 // helper functions.
100 void print_pretty_llr_vector(const float* llr_vec) const;
101};
102
103} // namespace code
104} // namespace fec
105} // namespace gr
106
107#endif /* INCLUDED_FEC_POLAR_DECODER_COMMON_H */
POLAR code common operations and attributes.
Definition: polar_common.h:57
Class holds common methods and attributes for different decoder implementations.
Definition: polar_decoder_common.h:40
bool set_frame_size(unsigned int frame_size)
Definition: polar_decoder_common.h:65
int get_output_size()
Definition: polar_decoder_common.h:64
polar_decoder_common(int block_size, int num_info_bits, std::vector< int > frozen_bit_positions, std::vector< char > frozen_bit_values)
void initialize_decoder(unsigned char *u, float *llrs, const float *input)
void print_pretty_llr_vector(const float *llr_vec) const
double rate()
Definition: polar_decoder_common.h:62
void butterfly(float *llrs, unsigned char *u, const int stage, const int u_num, const int row)
void even_u_values(unsigned char *u_even, const unsigned char *u, const int u_num)
void extract_info_bits(unsigned char *output, const unsigned char *input) const
void butterfly_generic(float *llrs, unsigned char *u, const int stage, const int u_num, const int row)
const bool is_frozen_bit(const int u_num) const
void butterfly_volk(float *llrs, unsigned char *u, const int stage, const int u_num, const int row)
unsigned char llr_bit_decision(const float llr) const
Definition: polar_decoder_common.h:75
const unsigned char next_frozen_bit()
void odd_xor_even_values(unsigned char *u_xor, const unsigned char *u, const int u_num)
int get_input_size()
Definition: polar_decoder_common.h:63
float llr_even(const float la, const float lb, const unsigned char f) const
float llr_odd(const float la, const float lb) const
Parent class for FECAPI objects.
Definition: generic_decoder.h:61
#define FEC_API
Definition: gr-fec/include/gnuradio/fec/api.h:30
Include this header to use the message passing features.
Definition: basic_block.h:45