rdsdemod.h

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// Copyright (C) 2015 F4EXB                                                      //
// written by Edouard Griffiths                                                  //
//                                                                               //
// This program 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 as version 3 of the License, or                  //
// (at your option) any later version.                                           //
//                                                                               //
// This program 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 V3 for more details.                               //
//                                                                               //
// You should have received a copy of the GNU General Public License             //
// along with this program. If not, see <http://www.gnu.org/licenses/>.          //


#ifndef PLUGINS_CHANNEL_BFM_RDSDEMOD_H_
#define PLUGINS_CHANNEL_BFM_RDSDEMOD_H_

#include <QObject>
//#include "util/udpsink.h" // UDP debug

#include "dsp/dsptypes.h"

class RDSDemod : public QObject
{
    Q_OBJECT
public:
    RDSDemod();
    ~RDSDemod();

    void setSampleRate(int srate);
    bool process(Real rdsSample, bool &bit);

    struct{
        Real acc;
        Real qua;
        Real fclk;
    } m_report;

protected:
    bool biphase(Real acc, bool &bit, Real d_cphi);
    Real filter_lp_2400_iq(Real in, int iqIndex);
    Real filter_lp_pll(Real input);
    int sign(Real a);

private:
    struct
    {
        double subcarr_phi;
        Real subcarr_bb[2];
        double clock_offset;
        double clock_phi;
        double prev_clock_phi;
        Real lo_clock;
        Real prev_lo_clock;
        Real prev_bb;
        double d_cphi;
        Real acc;
        int numsamples;
        Real prev_acc;
        int counter;
        int reading_frame;
        int tot_errs[2];
        int dbit;
    } m_parms;

    Real m_xv[2][2+1];
    Real m_yv[2][2+1];
    Real m_xw[1+1];
    Real m_yw[1+1];
    Real m_prev;

    int m_srate;

    static const Real m_pllBeta;
    static const Real m_fsc;
};

#endif /* PLUGINS_CHANNEL_BFM_RDSDEMOD_H_ */