hilbert_fc.h

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/* -*- c++ -*- */
/*
 * Copyright 2004,2012 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 */
 
#ifndef INCLUDED_FILTER_HILBERT_FC_H
#define INCLUDED_FILTER_HILBERT_FC_H
 
#include <gnuradio/fft/window.h>
#include <gnuradio/filter/api.h>
#include <gnuradio/filter/firdes.h>
#include <gnuradio/sync_block.h>
#include <gnuradio/types.h>
 
namespace gr {
namespace filter {
 
/*!
 * \brief Generate Analytic Signal.
 * \ingroup filter_blk
 *
 * \details
 * Real part of the output is an appropriately delayed version of the input while
 * the complex part of the output is the hilbert transform of the input.
 *
 * This is an indirect way of generating the hilbert transform of a signal.
 *
 * (https://en.wikipedia.org/wiki/Hilbert_transform#Analytic_representation)
 */
class FILTER_API hilbert_fc : virtual public sync_block
{
public:
    // gr::filter::hilbert_fc::sptr
    typedef std::shared_ptr<hilbert_fc> sptr;
 
    /*!
     * Build a Hilbert transformer filter block that generates the analytic signal.
     *
     * \param ntaps The number of taps for the filter.
     * \param window Window type (see fft::window::win_type) to use.
     * \param param Parameter value for a Kaiser/Exp/Gaussian/Tukey window.
     */
    static sptr make(unsigned int ntaps,
                     fft::window::win_type window = fft::window::win_type::WIN_HAMMING,
                     double param = 6.76);
};
 
} /* namespace filter */
} /* namespace gr */
 
#endif /* INCLUDED_FILTER_HILBERT_FC_H */