ofdm_frame_equalizer_vcvc.h

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/* -*- c++ -*- */
/* Copyright 2012 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * GNU Radio 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.
 *
 * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef INCLUDED_OFDM_FRAME_EQUALIZER_VCVC_H
#define INCLUDED_OFDM_FRAME_EQUALIZER_VCVC_H

#include <gnuradio/digital/api.h>
#include <gnuradio/digital/ofdm_equalizer_base.h>
#include <gnuradio/tagged_stream_block.h>

namespace gr {
namespace digital {

/*!
 * \brief OFDM frame equalizer
 * \ingroup ofdm_blk
 *
 * \details
 * Performs equalization in one or two dimensions on a tagged OFDM frame.
 *
 * This does two things:
 * First, it removes the coarse carrier offset. If a tag is found on the first
 * item with the key 'ofdm_sync_carr_offset', this is interpreted as the coarse
 * frequency offset in number of carriers.
 * Next, it performs equalization in one or two dimensions on a tagged OFDM frame.
 * The actual equalization is done by a ofdm_frame_equalizer object, outside of
 * the block.
 *
 * Note that the tag with the coarse carrier offset is not removed. Blocks
 * downstream from this block must not attempt to also correct this offset.
 *
 * Input: a tagged series of OFDM symbols.
 * Output: The same as the input, but equalized and frequency-corrected.
 */
class DIGITAL_API ofdm_frame_equalizer_vcvc : virtual public tagged_stream_block
{
public:
    typedef boost::shared_ptr<ofdm_frame_equalizer_vcvc> sptr;

    /*!
     * \param equalizer The equalizer object that will do the actual work
     * \param cp_len Length of the cyclic prefix in samples (required to correct the
     * frequency offset) \param tsb_key TSB key \param propagate_channel_state If true,
     * the channel state after the last symbol will be added to the first symbol as a tag
     * \param fixed_frame_len Set if the frame length is fixed. When this value is given,
     *                        the TSB tag key can be left empty, but it is useful even
     *                        when using tagged streams at the input.
     */
    static sptr make(ofdm_equalizer_base::sptr equalizer,
                     int cp_len,
                     const std::string& tsb_key = "frame_len",
                     bool propagate_channel_state = false,
                     int fixed_frame_len = 0);
};

} // namespace digital
} // namespace gr

#endif /* INCLUDED_OFDM_FRAME_EQUALIZER_VCVC_H */