ofdm_serializer_vcc.h

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/* -*- c++ -*- */
/* Copyright 2012 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 */
 
#ifndef INCLUDED_DIGITAL_OFDM_SERIALIZER_VCC_H
#define INCLUDED_DIGITAL_OFDM_SERIALIZER_VCC_H
 
#include <gnuradio/digital/api.h>
#include <gnuradio/digital/ofdm_carrier_allocator_cvc.h>
#include <gnuradio/tagged_stream_block.h>
 
namespace gr {
namespace digital {
 
/*!
 * \brief Serializes complex modulations symbols from OFDM sub-carriers
 * \ingroup ofdm_blk
 *
 * \details
 * This is the inverse block to the carrier_allocator_cvc. It outputs the
 * complex data symbols as a tagged stream, discarding the pilot symbols.
 *
 * If given, two different tags are parsed: The first key (\p len_tag_key)
 * specifies the number of OFDM symbols in the frame at the input. The
 * second key (\p packet_len_tag_key) specifies the number of complex symbols
 * that are coded into this frame. If given, this second key is then used
 * at the output, otherwise, \p len_tag_key is used.
 * If both are given, the packet length specifies the maximum number of
 * output items, and the frame length specifies the exact number of
 * consumed input items.
 *
 * It is possible to correct a carrier offset in this function by passing
 * another tag with said offset.
 *
 * Input: Complex vectors of length \p fft_len
 * Output: Complex scalars, in the same order as specified in occupied_carriers.
 */
class DIGITAL_API ofdm_serializer_vcc : virtual public tagged_stream_block
{
public:
    typedef std::shared_ptr<ofdm_serializer_vcc> sptr;
 
    /*!
     * \param fft_len FFT length
     * \param occupied_carriers See ofdm_carrier_allocator_cvc.
     * \param len_tag_key The key of the tag identifying the length of the input frame in
     * OFDM symbols. \param packet_len_tag_key The key of the tag identifying the number
     * of complex symbols in this packet. \param symbols_skipped If the first symbol is
     * not allocated as in \p occupied_carriers[0], set this \param carr_offset_key When
     * this block should correct a carrier offset, specify the tag key of the offset here
     * (not necessary if following an ofdm_frame_equalizer_vcvc) \param input_is_shifted
     * If the input has the DC carrier on index 0 (i.e. it is not FFT shifted), set this
     * to false
     */
    static sptr make(int fft_len,
                     const std::vector<std::vector<int>>& occupied_carriers,
                     const std::string& len_tag_key = "frame_len",
                     const std::string& packet_len_tag_key = "",
                     int symbols_skipped = 0,
                     const std::string& carr_offset_key = "",
                     bool input_is_shifted = true);
 
    /*!
     * \param allocator The carrier allocator block of which this shall be the inverse
     * \param packet_len_tag_key The key of the tag identifying the number of complex
     * symbols in this packet. \param symbols_skipped If the first symbol is not allocated
     * as in \p occupied_carriers[0], set this \param carr_offset_key When this block
     * should correct a carrier offset, specify the tag key of the offset here (not
     * necessary if following an ofdm_frame_equalizer_vcvc) \param input_is_shifted If the
     * input has the DC carrier on index 0 (i.e. it is not FFT shifted), set this to false
     */
    static sptr make(const gr::digital::ofdm_carrier_allocator_cvc::sptr& allocator,
                     const std::string& packet_len_tag_key = "",
                     int symbols_skipped = 0,
                     const std::string& carr_offset_key = "",
                     bool input_is_shifted = true);
};
 
} // namespace digital
} // namespace gr
 
#endif /* INCLUDED_DIGITAL_OFDM_SERIALIZER_VCC_H */