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Diffstat (limited to 'gr-fec/lib/ldpc_R_U_encoder_impl.cc')
| -rw-r--r-- | gr-fec/lib/ldpc_R_U_encoder_impl.cc | 193 |
1 files changed, 0 insertions, 193 deletions
diff --git a/gr-fec/lib/ldpc_R_U_encoder_impl.cc b/gr-fec/lib/ldpc_R_U_encoder_impl.cc deleted file mode 100644 index c8f884c9a0..0000000000 --- a/gr-fec/lib/ldpc_R_U_encoder_impl.cc +++ /dev/null @@ -1,193 +0,0 @@ -/* -*- c++ -*- */ -/* - * Copyright 2015 Free Software Foundation, Inc. - * - * This 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. - * - * This software 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 this software; see the file COPYING. If not, write to - * the Free Software Foundation, Inc., 51 Franklin Street, - * Boston, MA 02110-1301, USA. - */ - -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif - -#include <ldpc_R_U_encoder_impl.h> -#include <sstream> - -namespace gr { - namespace fec { - namespace code { - generic_encoder::sptr - ldpc_R_U_encoder::make(const ldpc_R_U_mtrx *H_obj) - { - return generic_encoder::sptr - (new ldpc_R_U_encoder_impl(H_obj)); - } - - ldpc_R_U_encoder_impl::ldpc_R_U_encoder_impl(const ldpc_R_U_mtrx *H_obj) - : generic_encoder("ldpc_R_U_encoder") - { - // LDPC parity check matrix to use for encoding - d_H = H_obj; - // Set frame size to k, the # of bits in the information word - // All buffers and settings will be based on this value. - set_frame_size(d_H->k()); - } - - ldpc_R_U_encoder_impl::~ldpc_R_U_encoder_impl() - { - } - - int - ldpc_R_U_encoder_impl::get_output_size() - { - return d_H->n(); - } - - int - ldpc_R_U_encoder_impl::get_input_size() - { - return d_frame_size; - } - - bool - ldpc_R_U_encoder_impl::set_frame_size(unsigned int frame_size) - { - bool ret = true; - // TODO add some bounds check here? The frame size is - // constant and specified by the size of the parity check - // matrix used for encoding. - d_frame_size = frame_size; - - return ret; - } - - double - ldpc_R_U_encoder_impl::rate() - { - return (d_H->n())/static_cast<double>(d_frame_size); - } - - gsl_matrix* - ldpc_R_U_encoder_impl::back_solve_mod2(const gsl_matrix *U, - const gsl_matrix *y) - { - // Exploit the fact that the matrix T is upper triangular and - // sparse. In the steps to find p1 and p2, back solve rather - // than do matrix multiplication to reduce number of - // operations required. - - // Form is Ux = y where U is upper triangular and y is column - // vector. Solve for x. - - // Allocate memory for the result - int num_rows = (*U).size1; - int num_cols_U = (*U).size2; - gsl_matrix *x = gsl_matrix_alloc(num_rows,1); - - // Back solve - for (int i = num_rows-1; i >= 0; i--) { - // x[i] = y[i] - gsl_matrix_set(x, i, 0, gsl_matrix_get(y, i, 0)); - - int j; - for (j = i+1; j < num_cols_U; j++) { - int U_i_j = gsl_matrix_get(U, i, j); - int x_i = gsl_matrix_get(x, i, 0); - int x_j = gsl_matrix_get(x, j, 0); - int temp1 = (U_i_j * x_j) % 2; - int temp2 = (x_i + temp1) % 2; - gsl_matrix_set(x, i, 0, temp2); - } - // Perform x[i] /= U[i,i], GF(2) operations - int U_i_i = gsl_matrix_get(U, i, i); - int x_i = gsl_matrix_get(x, i, 0); - if (x_i==0 && U_i_i==1) - gsl_matrix_set(x, i, 0, 0); - else if (x_i==0 && U_i_i==0) - gsl_matrix_set(x, i, 0, 0); - else if (x_i==1 && U_i_i==1) - gsl_matrix_set(x, i, 0, 1); - else if (x_i==1 && U_i_i==0) - std::cout << "Error in " - << " ldpc_R_U_encoder_impl::back_solve_mod2," - << " division not defined.\n"; - else - std::cout << "Error in ldpc_R_U_encoder_impl::back_solve_mod2\n"; - } - return x; - } - - void - ldpc_R_U_encoder_impl::generic_work(void *inbuffer, - void *outbuffer) - { - // Populate the information word - const unsigned char *in = (const unsigned char *)inbuffer; - unsigned int index, k = d_H->k(); - gsl_matrix *s = gsl_matrix_alloc(k, 1); - for (index = 0; index < k; index++) { - double value = static_cast<double>(in[index]); - gsl_matrix_set(s, index, 0, value); - } - - // Solve for p2 (parity part). By using back substitution, - // the overall complexity of determining p2 is O(n + g^2). - gsl_matrix *temp1 = d_H->mult_matrices_mod2(d_H->B(), s); - gsl_matrix *temp2 = back_solve_mod2(d_H->T(),temp1); - gsl_matrix *temp3 = d_H->mult_matrices_mod2(d_H->E(), temp2); - gsl_matrix *temp4 = d_H->mult_matrices_mod2(d_H->D(), s); - gsl_matrix *temp5 = d_H->add_matrices_mod2(temp4, temp3); - gsl_matrix *p2 = d_H->mult_matrices_mod2( - d_H->phi_inverse(), temp5); - - // Solve for p1 (parity part). By using back substitution, - // the overall complexity of determining p1 is O(n). - gsl_matrix *temp6 = d_H->mult_matrices_mod2(d_H->A(), p2); - gsl_matrix *temp7 = d_H->add_matrices_mod2(temp6, temp1); - gsl_matrix *p1 = back_solve_mod2(d_H->T(),temp7); - - // Populate the codeword to be output - unsigned int p1_length = (*p1).size1; - unsigned int p2_length = (*p2).size1; - unsigned char *out = (unsigned char*)outbuffer; - for (index = 0; index < p1_length; index++) { - int value = gsl_matrix_get(p1, index, 0); - out[index] = value; - } - for (index = 0; index < p2_length; index++) { - int value = gsl_matrix_get(p2, index, 0); - out[p1_length+index] = value; - } - for (index = 0; index < k; index++) { - int value = gsl_matrix_get(s, index, 0); - out[p1_length+p2_length+index] = value; - } - - // Free memory - gsl_matrix_free(temp1); - gsl_matrix_free(temp2); - gsl_matrix_free(temp3); - gsl_matrix_free(temp4); - gsl_matrix_free(temp5); - gsl_matrix_free(temp6); - gsl_matrix_free(temp7); - gsl_matrix_free(p1); - gsl_matrix_free(p2); - gsl_matrix_free(s); - - } - } /* namespace code */ - } /* namespace fec */ -} /* namespace gr */
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