/* -*- c++ -*- */ /* * Copyright 2015 Free Software Foundation, Inc. * * This file is part of GNU Radio * * SPDX-License-Identifier: GPL-3.0-or-later * */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include <gnuradio/fec/polar_decoder_sc.h> #include <gnuradio/io_signature.h> #include <volk/volk.h> #include <cmath> #include <cstdio> namespace gr { namespace fec { namespace code { generic_decoder::sptr polar_decoder_sc::make(int block_size, int num_info_bits, std::vector<int> frozen_bit_positions, std::vector<uint8_t> frozen_bit_values) { return generic_decoder::sptr(new polar_decoder_sc( block_size, num_info_bits, frozen_bit_positions, frozen_bit_values)); } polar_decoder_sc::polar_decoder_sc(int block_size, int num_info_bits, std::vector<int> frozen_bit_positions, std::vector<uint8_t> frozen_bit_values) : polar_decoder_common( block_size, num_info_bits, frozen_bit_positions, frozen_bit_values), d_llr_vec(block_size * (block_power() + 1)), d_u_hat_vec(block_size * (block_power() + 1)) { } polar_decoder_sc::~polar_decoder_sc() {} void polar_decoder_sc::generic_work(void* in_buffer, void* out_buffer) { const float* in = (const float*)in_buffer; unsigned char* out = (unsigned char*)out_buffer; initialize_decoder(d_u_hat_vec.data(), d_llr_vec.data(), in); sc_decode(d_llr_vec.data(), d_u_hat_vec.data()); extract_info_bits(out, d_u_hat_vec.data()); } void polar_decoder_sc::sc_decode(float* llrs, unsigned char* u) { for (int i = 0; i < block_size(); i++) { butterfly(llrs, u, 0, i, i); u[i] = retrieve_bit_from_llr(llrs[i], i); } } unsigned char polar_decoder_sc::retrieve_bit_from_llr(float llr, const int pos) { if (is_frozen_bit(pos)) { return next_frozen_bit(); } return llr_bit_decision(llr); } } /* namespace code */ } /* namespace fec */ } /* namespace gr */