sdrangelove/plugins/channel/nfm/nfmdemod.h

133 lines
3.8 KiB
C++

///////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2012 maintech GmbH, Otto-Hahn-Str. 15, 97204 Hoechberg, Germany //
// written by Christian Daniel //
// //
// 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 //
// //
// 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 INCLUDE_NFMDEMOD_H
#define INCLUDE_NFMDEMOD_H
#include <vector>
#include "dsp/samplesink.h"
#include "dsp/nco.h"
#include "dsp/interpolator.h"
#include "dsp/lowpass.h"
#include "dsp/movingaverage.h"
#include "audio/audiofifo.h"
#include "util/message.h"
class AudioFifo;
class NFMDemod : public SampleSink {
public:
NFMDemod(AudioFifo* audioFifo, SampleSink* sampleSink);
~NFMDemod();
void configure(MessageQueue* messageQueue, Real rfBandwidth, Real afBandwidth, Real volume, Real squelch);
void feed(SampleVector::const_iterator begin, SampleVector::const_iterator end, bool firstOfBurst);
void start();
void stop();
bool handleMessage(Message* cmd);
private:
class MsgConfigureNFMDemod : public Message {
MESSAGE_CLASS_DECLARATION(MsgConfigureNFMDemod)
public:
Real getRFBandwidth() const { return m_rfBandwidth; }
Real getAFBandwidth() const { return m_afBandwidth; }
Real getVolume() const { return m_volume; }
Real getSquelch() const { return m_squelch; }
static MsgConfigureNFMDemod* create(Real rfBandwidth, Real afBandwidth, Real volume, Real squelch)
{
return new MsgConfigureNFMDemod(rfBandwidth, afBandwidth, volume, squelch);
}
private:
Real m_rfBandwidth;
Real m_afBandwidth;
Real m_volume;
Real m_squelch;
MsgConfigureNFMDemod(Real rfBandwidth, Real afBandwidth, Real volume, Real squelch) :
Message(),
m_rfBandwidth(rfBandwidth),
m_afBandwidth(afBandwidth),
m_volume(volume),
m_squelch(squelch)
{ }
};
struct AudioSample {
qint16 l;
qint16 r;
};
typedef std::vector<AudioSample> AudioVector;
enum RateState {
RSInitialFill,
RSRunning
};
struct Config {
int m_inputSampleRate;
qint64 m_inputFrequencyOffset;
Real m_rfBandwidth;
Real m_afBandwidth;
Real m_squelch;
Real m_volume;
quint32 m_audioSampleRate;
Config() :
m_inputSampleRate(-1),
m_inputFrequencyOffset(0),
m_rfBandwidth(-1),
m_afBandwidth(-1),
m_squelch(0),
m_volume(0),
m_audioSampleRate(0)
{ }
};
Config m_config;
Config m_running;
NCO m_nco;
Real m_interpolatorRegulation;
Interpolator m_interpolator;
Real m_interpolatorDistance;
Real m_interpolatorDistanceRemain;
Lowpass<Real> m_lowpass;
Real m_squelchLevel;
int m_squelchState;
Real m_lastArgument;
Complex m_lastSample;
MovingAverage m_movingAverage;
AudioVector m_audioBuffer;
uint m_audioBufferFill;
AudioFifo* m_audioFifo;
SampleSink* m_sampleSink;
SampleVector m_sampleBuffer;
void apply();
};
#endif // INCLUDE_NFMDEMOD_H