GNU Radio 3.7.1 C++ API
ofdm_frame_equalizer_vcvc.h
Go to the documentation of this file.
00001 /* -*- c++ -*- */
00002 /* Copyright 2012 Free Software Foundation, Inc.
00003  * 
00004  * This file is part of GNU Radio
00005  * 
00006  * GNU Radio is free software; you can redistribute it and/or modify
00007  * it under the terms of the GNU General Public License as published by
00008  * the Free Software Foundation; either version 3, or (at your option)
00009  * any later version.
00010  * 
00011  * GNU Radio is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  * GNU General Public License for more details.
00015  * 
00016  * You should have received a copy of the GNU General Public License
00017  * along with GNU Radio; see the file COPYING.  If not, write to
00018  * the Free Software Foundation, Inc., 51 Franklin Street,
00019  * Boston, MA 02110-1301, USA.
00020  */
00021 
00022 #ifndef INCLUDED_OFDM_FRAME_EQUALIZER_VCVC_H
00023 #define INCLUDED_OFDM_FRAME_EQUALIZER_VCVC_H
00024 
00025 #include <gnuradio/digital/api.h>
00026 #include <gnuradio/digital/ofdm_equalizer_base.h>
00027 #include <gnuradio/tagged_stream_block.h>
00028 
00029 namespace gr {
00030   namespace digital {
00031 
00032     /*!
00033      * \brief OFDM frame equalizer
00034      * \ingroup ofdm_blk
00035      *
00036      * \details
00037      * Performs equalization in one or two dimensions on a tagged OFDM frame.
00038      *
00039      * This does two things:
00040      * First, it removes the coarse carrier offset. If a tag is found on the first
00041      * item with the key 'ofdm_sync_carr_offset', this is interpreted as the coarse
00042      * frequency offset in number of carriers.
00043      * Next, it performs equalization in one or two dimensions on a tagged OFDM frame.
00044      * The actual equalization is done by a ofdm_frame_equalizer object, outside of
00045      * the block.
00046      *
00047      * Note that the tag with the coarse carrier offset is not removed. Blocks
00048      * downstream from this block must not attempt to also correct this offset.
00049      *
00050      * Input: a tagged series of OFDM symbols.
00051      * Output: The same as the input, but equalized and frequency-corrected.
00052      */
00053     class DIGITAL_API ofdm_frame_equalizer_vcvc : virtual public tagged_stream_block
00054     {
00055      public:
00056       typedef boost::shared_ptr<ofdm_frame_equalizer_vcvc> sptr;
00057 
00058       /*!
00059        * \param equalizer The equalizer object that will do the actual work
00060        * \param cp_len Length of the cyclic prefix in samples (required to correct the frequency offset)
00061        * \param len_tag_key Length tag key
00062        * \param propagate_channel_state If true, the channel state after the last symbol
00063        *                                will be added to the first symbol as a tag
00064        * \param fixed_frame_len Set if the frame length is fixed throughout, 
00065        *                        helps with book keeping.
00066        */
00067       static sptr make(
00068            ofdm_equalizer_base::sptr equalizer,
00069            int cp_len,
00070            const std::string &len_tag_key = "frame_len",
00071            bool propagate_channel_state=false,
00072            int fixed_frame_len=0
00073       );
00074     };
00075 
00076   } // namespace digital
00077 } // namespace gr
00078 
00079 #endif /* INCLUDED_OFDM_FRAME_EQUALIZER_VCVC_H */
00080