ldpc_gen_mtrx_encoder.h

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/* -*- 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.
 */

#ifndef INCLUDED_FEC_LDPC_GEN_MTRX_ENCODER_H
#define INCLUDED_FEC_LDPC_GEN_MTRX_ENCODER_H

#include <gnuradio/fec/api.h>
#include <gnuradio/fec/generic_encoder.h>
#include <gnuradio/fec/ldpc_G_matrix.h>

namespace gr {
namespace fec {
namespace code {

/*!
 * \brief LDPC generator matrix encoder
 * \ingroup error_coding_blk
 *
 * \details
 * A standard encoder class. This method is discussed in many
 * textbooks; one is: Turbo Coding for Satellite and Wireless
 * Communications by Soleymani, Gao, and Vilaipornsawai.
 * Given a generator matrix in systematic form,
 * \f$\mathbf{G}=\left[\mathbf{I}_{k}|\mathbf{P}\right]\f$,
 * where \f$\mathbf{I}_{k}\f$ is the identity matrix and
 * \f$\mathbf{P}\f$ is the parity submatrix, the information
 * word \f$\bar{s}\f$ is encoded into a codeword
 * \f$\overline{x}\f$ via:
 * \f[\overline{x}=\mathbf{G}^{T}\bar{s}\f]
 */
class FEC_API ldpc_gen_mtrx_encoder : virtual public generic_encoder
{
public:
    /*!
     * \brief Build an encoding FEC API object.
     * \param G_obj The ldpc_G_matrix object to use for
     *              encoding.
     */
    static generic_encoder::sptr make(const code::ldpc_G_matrix::sptr G_obj);

    /*!
     * \brief  Sets the uncoded frame size to \p frame_size.
     * \details
     * Sets the uncoded frame size to \p frame_size. If \p
     * frame_size is greater than the value given to the
     * constructor, the frame size will be capped by that initial
     * value and this function will return false. Otherwise, it
     * returns true.
     */
    virtual bool set_frame_size(unsigned int frame_size) = 0;

    //! Returns the coding rate of this encoder.
    virtual double rate() = 0;
};
} /* namespace code */
} /* namespace fec */
} /* namespace gr */

#endif /* INCLUDED_FEC_LDPC_GEN_MTRX_ENCODER_H */