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/* -*- c++ -*- */
/*
* Copyright 2014 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_DIGITAL_MSK_TIMING_RECOVERY_CC_H
#define INCLUDED_DIGITAL_MSK_TIMING_RECOVERY_CC_H
#include <gnuradio/digital/api.h>
#include <gnuradio/block.h>
namespace gr {
namespace digital {
/*!
* \brief MSK/GMSK timing recovery
* \ingroup synchronizers_blk
*
* This block performs timing synchronization on CPM modulations using a
* fourth-order nonlinearity feedback method which is non-data-aided. The
* block does not require prior phase synchronization but is relatively
* sensitive to frequency offset (keep offset to 0.1x symbol rate).
*
* For details on the algorithm, see:
* A.N. D'Andrea, U. Mengali, R. Reggiannini: A digital approach to clock
* recovery in generalized minimum shift keying. IEEE Transactions on
* Vehicular Technology, Vol. 39, Issue 3.
*/
class DIGITAL_API msk_timing_recovery_cc : virtual public gr::block
{
public:
typedef boost::shared_ptr<msk_timing_recovery_cc> sptr;
/*!
* \brief Make an MSK timing recovery block.
*
* \param sps: Samples per symbol
* \param gain: Loop gain of timing error filter (try 0.05)
* \param limit: Relative limit of timing error (try 0.1 for 10% error max)
* \param osps: Output samples per symbol
*
*/
static sptr make(float sps, float gain, float limit, int osps);
virtual void set_gain(float gain)=0;
virtual float get_gain(void)=0;
virtual void set_limit(float limit)=0;
virtual float get_limit(void)=0;
virtual void set_sps(float sps)=0;
virtual float get_sps(void)=0;
};
} // namespace digital
} // namespace gr
#endif /* INCLUDED_DIGITAL_MSK_TIMING_RECOVERY_CC_H */
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