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Changed NFM RF threshold squelch for after demod squelch

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This commit is contained in:
f4exb
2015-06-19 08:27:29 +02:00
parent 70cce80995
commit e66d9a417f
6 changed files with 370 additions and 55 deletions
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plugins/channel/nfm/nfmdemod.cpp
+55 -52
View File
@@ -26,11 +26,15 @@
#include <iostream>
static const Real afSqTones[2] = {2000.0, 8000.0};
MESSAGE_CLASS_DEFINITION(NFMDemod::MsgConfigureNFMDemod, Message)
NFMDemod::NFMDemod(AudioFifo* audioFifo, SampleSink* sampleSink) :
m_ctcssIndex(0),
m_sampleCount(0),
m_afSquelch(2, afSqTones),
m_squelchOpen(false),
m_sampleSink(sampleSink),
m_audioFifo(audioFifo)
{
@@ -38,7 +42,7 @@ NFMDemod::NFMDemod(AudioFifo* audioFifo, SampleSink* sampleSink) :
m_config.m_inputFrequencyOffset = 0;
m_config.m_rfBandwidth = 12500;
m_config.m_afBandwidth = 3000;
m_config.m_squelch = -40.0;
m_config.m_squelch = -30.0;
m_config.m_volume = 2.0;
m_config.m_audioSampleRate = 48000;
@@ -52,6 +56,8 @@ NFMDemod::NFMDemod(AudioFifo* audioFifo, SampleSink* sampleSink) :
m_AGC.resize(4096, m_agcLevel, 0, 0.1*m_agcLevel);
m_ctcssDetector.setCoefficients(3000, 6000.0); // 0.5s / 2 Hz resolution
m_afSquelch.setCoefficients(24, 48000.0, 1, 1); // 4000 Hz span, 250us
m_afSquelch.setThreshold(0.001);
}
NFMDemod::~NFMDemod()
@@ -109,56 +115,52 @@ void NFMDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iter
if(m_interpolator.interpolate(&m_interpolatorDistanceRemain, c, &ci)) {
m_sampleBuffer.push_back(Sample(ci.real() * 32767.0, ci.imag() * 32767.0));
m_movingAverage.feed(ci.real() * ci.real() + ci.imag() * ci.imag());
if(m_movingAverage.average() >= m_squelchLevel)
m_squelchState = m_running.m_audioSampleRate/ 20;
qint16 sample;
if(m_squelchState > 0)
m_AGC.feed(abs(ci));
ci *= (m_agcLevel / m_AGC.getValue());
// demod
/*
Real argument = arg(ci);
Real demod = argument - m_lastArgument;
m_lastArgument = argument;
*/
/*
// Original NFM
Complex d = conj(m_m1Sample) * ci;
Real demod = atan2(d.imag(), d.real());
demod /= M_PI;
*/
/*
Real argument1 = arg(ci);//atan2(ci.imag(), ci.real());
Real argument2 = m_lastSample.real();
Real demod = angleDist(argument2, argument1);
m_lastSample = Complex(argument1, 0);
*/
// Alternative without atan - needs AGC
// http://www.embedded.com/design/configurable-systems/4212086/DSP-Tricks--Frequency-demodulation-algorithms-
Real ip = ci.real() - m_m2Sample.real();
Real qp = ci.imag() - m_m2Sample.imag();
Real h1 = m_m1Sample.real() * qp;
Real h2 = m_m1Sample.imag() * ip;
Real demod = (h1 - h2) * 10000;
m_m2Sample = m_m1Sample;
m_m1Sample = ci;
m_sampleCount++;
// AF processing
if(m_afSquelch.analyze(&demod)) {
m_squelchOpen = m_afSquelch.open();
}
if (m_squelchOpen)
{
m_squelchState--;
m_AGC.feed(abs(ci));
ci *= (m_agcLevel / m_AGC.getValue());
// demod
/*
Real argument = arg(ci);
Real demod = argument - m_lastArgument;
m_lastArgument = argument;
*/
/*
// Original NFM
Complex d = conj(m_m1Sample) * ci;
Real demod = atan2(d.imag(), d.real());
demod /= M_PI;
*/
/*
Real argument1 = arg(ci);//atan2(ci.imag(), ci.real());
Real argument2 = m_lastSample.real();
Real demod = angleDist(argument2, argument1);
m_lastSample = Complex(argument1, 0);
*/
// Alternative without atan - needs AGC
// http://www.embedded.com/design/configurable-systems/4212086/DSP-Tricks--Frequency-demodulation-algorithms-
Real ip = ci.real() - m_m2Sample.real();
Real qp = ci.imag() - m_m2Sample.imag();
Real h1 = m_m1Sample.real() * qp;
Real h2 = m_m1Sample.imag() * ip;
Real demod = (h1 - h2) * 10000;
m_m2Sample = m_m1Sample;
m_m1Sample = ci;
m_sampleCount++;
// AF processing
//demod = m_lowpass.filter(demod);
//sample = demod * 32700;
Real ctcss_sample = m_lowpass.filter(demod);
if ((m_sampleCount & 7) == 7) // decimate 48k -> 6k
@@ -186,7 +188,7 @@ void NFMDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iter
if (m_ctcssIndexSelected && (m_ctcssIndexSelected != m_ctcssIndex))
{
sample = 0.0;
sample = 0;
}
else
{
@@ -234,7 +236,6 @@ void NFMDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iter
void NFMDemod::start()
{
m_squelchState = 0;
m_audioFifo->clear();
m_interpolatorRegulation = 0.9999;
m_interpolatorDistance = 1.0;
@@ -292,8 +293,10 @@ void NFMDemod::apply()
}
if(m_config.m_squelch != m_running.m_squelch) {
m_squelchLevel = pow(10.0, m_config.m_squelch / 20.0);
m_squelchLevel = pow(10.0, m_config.m_squelch / 10.0);
m_squelchLevel *= m_squelchLevel;
m_afSquelch.setThreshold(m_squelchLevel);
m_afSquelch.reset();
}
m_running.m_inputSampleRate = m_config.m_inputSampleRate;
plugins/channel/nfm/nfmdemod.h
+5 -2
View File
@@ -27,6 +27,7 @@
#include "dsp/movingaverage.h"
#include "dsp/agc.h"
#include "dsp/ctcssdetector.h"
#include "dsp/afsquelch.h"
#include "audio/audiofifo.h"
#include "util/message.h"
@@ -136,8 +137,10 @@ private:
int m_ctcssIndexSelected;
int m_sampleCount;
Real m_squelchLevel;
int m_squelchState;
double m_squelchLevel;
//int m_squelchState;
AFSquelch m_afSquelch;
bool m_squelchOpen;
Real m_lastArgument;
Complex m_m1Sample;
plugins/channel/nfm/nfmdemodgui.ui
+8 -1
View File
@@ -253,10 +253,17 @@
</widget>
</item>
<item row="5" column="1">
<widget class="QComboBox" name="ctcss"/>
<widget class="QComboBox" name="ctcss">
<property name="toolTip">
<string>Set CTCSS</string>
</property>
</widget>
</item>
<item row="5" column="2">
<widget class="QLabel" name="ctcssText">
<property name="toolTip">
<string>CTCSS detected</string>
</property>
<property name="text">
<string>--</string>
</property>