mirror of
https://github.com/f4exb/sdrangel.git
synced 2024-11-08 17:46:03 -05:00
95 lines
3.7 KiB
C++
95 lines
3.7 KiB
C++
//////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
// Copyright (C) 2015-2020 Edouard Griffiths, F4EXB //
|
|
// //
|
|
// See: http://www.embedded.com/design/connectivity/4025660/Detecting-CTCSS-tones-with-Goertzel-s-algorithm //
|
|
// //
|
|
// 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 INCLUDE_GPL_DSP_CTCSSDETECTOR_H_
|
|
#define INCLUDE_GPL_DSP_CTCSSDETECTOR_H_
|
|
|
|
#include "dsp/dsptypes.h"
|
|
#include "export.h"
|
|
#include "ctcssfrequencies.h"
|
|
|
|
/** CTCSSDetector: Continuous Tone Coded Squelch System
|
|
* tone detector class based on the Modified Goertzel
|
|
* algorithm.
|
|
*/
|
|
class SDRBASE_API CTCSSDetector {
|
|
public:
|
|
CTCSSDetector();
|
|
virtual ~CTCSSDetector();
|
|
|
|
// setup the basic parameters and coefficients
|
|
void setCoefficients(
|
|
int N, // the algorithm "block" size
|
|
int sampleRate // input signal sample rate
|
|
);
|
|
|
|
// set the detection threshold
|
|
void setThreshold(double thold);
|
|
|
|
// analyze a sample set and optionally filter the tone frequencies.
|
|
bool analyze(Real *sample); // input signal sample
|
|
|
|
// get the number of defined tones.
|
|
int getNTones() const {
|
|
return CTCSSFrequencies::m_nbFreqs;
|
|
}
|
|
|
|
// get the tone set
|
|
const Real *getToneSet() const {
|
|
return CTCSSFrequencies::m_Freqs;
|
|
}
|
|
|
|
// get the currently detected tone, if any
|
|
bool getDetectedTone(int &maxTone) const
|
|
{
|
|
maxTone = m_maxPowerIndex;
|
|
return m_toneDetected;
|
|
}
|
|
|
|
// Get the max m_power at the detected tone.
|
|
Real getMaxPower() const {
|
|
return m_maxPower;
|
|
}
|
|
|
|
void reset(); // reset the analysis algorithm
|
|
|
|
protected:
|
|
// Override these to change behavior of the detector
|
|
virtual void initializePower();
|
|
virtual void evaluatePower();
|
|
void feedback(Real sample);
|
|
void feedForward();
|
|
|
|
private:
|
|
int m_N;
|
|
int m_sampleRate;
|
|
int m_samplesProcessed;
|
|
int m_maxPowerIndex;
|
|
bool m_toneDetected;
|
|
Real m_maxPower;
|
|
Real *m_k;
|
|
Real *m_coef;
|
|
Real *m_u0;
|
|
Real *m_u1;
|
|
Real *m_power;
|
|
};
|
|
|
|
|
|
#endif /* INCLUDE_GPL_DSP_CTCSSDETECTOR_H_ */
|