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330 WIP - P25 C4FM decoder fully functional using DQPSK decoder and

Browse Source 
new symbol timing error detector.  Each component now has a subclass
that supports instrumentation for use with the DemodulatorViewerFX
application.
This commit is contained in:
Denny
2018-02-25 08:56:34 -05:00
parent a0630102e6
commit 148ddd0bd5
23 changed files with 623 additions and 1302 deletions
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6
src/main/java/io/github/dsheirer/dsp/filter/design/FilterViewer.java
View File

@@ -50,12 +50,12 @@ public class FilterViewer extends Application
// .stopBandRipple(0.008)
// .build();
FIRFilterSpecification specification = FIRFilterSpecification.lowPassBuilder()
.sampleRate((int)48000.0)
.passBandCutoff(2880)
.sampleRate(48000)
.passBandCutoff(5100)
.passBandAmplitude(1.0)
.passBandRipple(0.01)
.stopBandAmplitude(0.0)
.stopBandStart(3600)
.stopBandStart(6500)
.stopBandRipple(0.01)
.build();

235
src/main/java/io/github/dsheirer/dsp/psk/DQPSKDemodulator.java
View File

@@ -15,7 +15,6 @@
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.dsp.psk.pll.CostasLoop;
import io.github.dsheirer.dsp.psk.pll.IPhaseLockedLoop;
import io.github.dsheirer.dsp.symbol.Dibit;
import io.github.dsheirer.sample.Listener;
@@ -28,70 +27,46 @@ import org.slf4j.LoggerFactory;
public class DQPSKDemodulator implements ComplexSampleListener
{
private final static Logger mLog = LoggerFactory.getLogger(DQPSKDemodulator.class);
private InterpolatingSymbolBuffer2 mInterpolatingSymbolBuffer;
private IPhaseLockedLoop mPLL;
protected InterpolatingSampleBuffer mInterpolatingSampleBuffer;
protected IPhaseLockedLoop mPLL;
protected IQPSKSymbolDecoder mDQPSKSymbolDecoder;
private ISymbolPhaseErrorCalculator mSymbolPhaseErrorCalculator;
private IQPSKSymbolDecoder mDQPSKSymbolDecoder;
// private GardnerDetector mGardnerDetector = new GardnerDetector();
private EarlyLateDetector mEarlyLateDetector = new EarlyLateDetector();
private EarlyLateDetector2 mEarlyLateDetector2 = new EarlyLateDetector2();
private Listener<Complex> mSymbolListener;
private Listener<Double> mPLLErrorListener;
private Listener<Double> mPLLFrequencyListener;
private Listener<Double> mSamplesPerSymbolListener;
private Listener<Dibit> mDibitListener;
private Listener<SymbolDecisionData2> mSymbolDecisionDataListener;
private DQPSKTimingErrorDetector mDQPSKTimingErrorDetector = new DQPSKTimingErrorDetector();
private Complex mReceivedSample = new Complex(0, 0);
private Complex mPreviousPrecedingSample = new Complex(0, 0);
private Complex mPreviousCurrentSample = new Complex(0, 0);
private Complex mPreviousFollowingSample = new Complex(0, 0);
private Complex mCurrentPrecedingSample = new Complex(0, 0);
private Complex mCurrentCurrentSample = new Complex(0, 0);
private Complex mCurrentFollowingSample = new Complex(0, 0);
private Complex mPrecedingSample = new Complex(0, 0);
private Complex mCurrentSample = new Complex(0, 0);
private Complex mPrecedingSymbol = new Complex(0, 0);
private Complex mCurrentSymbol = new Complex(0, 0);
private Complex mFollowingSymbol = new Complex(0, 0);
protected Complex mCurrentSymbol = new Complex(0, 0);
private float mPhaseError;
protected float mPhaseError;
private float mSymbolTimingError;
private double mSampleRate;
private Listener<Dibit> mDibitListener;
/**
* Decoder for Quaternary Phase Shift Keying (QPSK) and Differential QPSK (DQPSK). This decoder uses both a
* phase-locked loop and a gardner symbol timing error detector to automatically align to the incoming carrier
* frequency and to adjust for any changes in symbol timing.
* Decoder for Differential Quaternary Phase Shift Keying (DQPSK). This decoder uses both a Costas Loop (PLL) and
* a custom DQPSK symbol timing error detector to automatically align to the incoming carrier frequency and to
* adjust for any changes in symbol timing.
*
* This detector is optimized for constant amplitude DQPSK symbols like C4FM.
*
* @param phaseLockedLoop for tracking carrier frequency error
* @param symbolPhaseErrorCalculator to calculate symbol phase errors and optionally adjust for differential encoding
* @param symbolPhaseErrorCalculator to calculate symbol phase errors to apply against the PLL
* @param symbolDecoder to decode demodulated symbols into dibits
* @param sampleRate of the incoming complex sample stream
* @param symbolRate of the decoded QPSK symbols.
*/
public DQPSKDemodulator(IPhaseLockedLoop phaseLockedLoop, ISymbolPhaseErrorCalculator symbolPhaseErrorCalculator,
IQPSKSymbolDecoder symbolDecoder, double sampleRate, double symbolRate)
IQPSKSymbolDecoder symbolDecoder, InterpolatingSampleBuffer interpolatingSampleBuffer)
{
if(sampleRate < (symbolRate * 2))
{
throw new IllegalArgumentException("Sample rate [" + sampleRate +
"] must be at least 2 x symbol rate [" + symbolRate + "]");
}
mSampleRate = sampleRate;
mPLL = phaseLockedLoop;
mSymbolPhaseErrorCalculator = symbolPhaseErrorCalculator;
mDQPSKSymbolDecoder = symbolDecoder;
float samplesPerSymbol = (float)(sampleRate / symbolRate);
mInterpolatingSymbolBuffer = new InterpolatingSymbolBuffer2(samplesPerSymbol);
mInterpolatingSampleBuffer = interpolatingSampleBuffer;
}
/**
* Submits a buffer containing complex samples for decoding
* Processes a (filtered) buffer containing complex samples for decoding
* @param complexBuffer with complex samples
*/
public void receive(ComplexBuffer complexBuffer)
@@ -105,7 +80,7 @@ public class DQPSKDemodulator implements ComplexSampleListener
}
/**
* Submits a complex sample for decoding.
* Processes a complex sample for decoding. Once sufficient samples are buffered, a symbol decision is made.
* @param inphase value for the sample
* @param quadrature value for the sample
*/
@@ -118,109 +93,64 @@ public class DQPSKDemodulator implements ComplexSampleListener
//Mix current sample with costas loop to remove any rotation that is present from a mis-tuned carrier frequency
mReceivedSample.multiply(mPLL.incrementAndGetCurrentVector());
mInterpolatingSymbolBuffer.receive(mReceivedSample);
//Store the sample in the interpolating buffer
mInterpolatingSampleBuffer.receive(mReceivedSample);
//Calculate the symbol once we've stored enough samples
if(mInterpolatingSymbolBuffer.hasSymbol())
if(mInterpolatingSampleBuffer.hasSymbol())
{
//Get middle and current samples from the interpolating buffer
mCurrentPrecedingSample = mInterpolatingSymbolBuffer.getPreceedingSample();
mCurrentCurrentSample = mInterpolatingSymbolBuffer.getCurrentSample();
mCurrentFollowingSample = mInterpolatingSymbolBuffer.getFollowingSample();
//Eye diagram listener
if(mSymbolDecisionDataListener != null)
{
mSymbolDecisionDataListener.receive(mInterpolatingSymbolBuffer.getSymbolDecisionData());
}
//Calculate preceding, current and following symbols as the delta rotation compared to the previous samples
mPrecedingSymbol.setInphase(Complex.multiplyInphase(mCurrentPrecedingSample.inphase(), mCurrentPrecedingSample.quadrature(),
mPreviousPrecedingSample.inphase(), -mPreviousPrecedingSample.quadrature()));
mPrecedingSymbol.setQuadrature(Complex.multiplyQuadrature(mCurrentPrecedingSample.inphase(), mCurrentPrecedingSample.quadrature(),
mPreviousPrecedingSample.inphase(), -mPreviousPrecedingSample.quadrature()));
mCurrentSymbol.setInphase(Complex.multiplyInphase(mCurrentCurrentSample.inphase(), mCurrentCurrentSample.quadrature(),
mPreviousCurrentSample.inphase(), -mPreviousCurrentSample.quadrature()));
mCurrentSymbol.setQuadrature(Complex.multiplyQuadrature(mCurrentCurrentSample.inphase(), mCurrentCurrentSample.quadrature(),
mPreviousCurrentSample.inphase(), -mPreviousCurrentSample.quadrature()));
mFollowingSymbol.setInphase(Complex.multiplyInphase(mCurrentFollowingSample.inphase(), mCurrentFollowingSample.quadrature(),
mPreviousFollowingSample.inphase(), -mPreviousFollowingSample.quadrature()));
mFollowingSymbol.setQuadrature(Complex.multiplyQuadrature(mCurrentFollowingSample.inphase(), mCurrentFollowingSample.quadrature(),
mPreviousFollowingSample.inphase(), -mPreviousFollowingSample.quadrature()));
//Set gain to unity before we calculate the error value
mPrecedingSymbol.normalize();
mCurrentSymbol.normalize();
mFollowingSymbol.normalize();
//Send to an external constellation symbol listener when registered
if(mSymbolListener != null)
{
mSymbolListener.receive(mCurrentSymbol);
}
//Symbol timing error calculations
mSymbolTimingError = mEarlyLateDetector.getError(mPrecedingSymbol, mCurrentSymbol, mFollowingSymbol);
mSymbolTimingError = GardnerDetector.clip(mSymbolTimingError, 0.5f);
mInterpolatingSymbolBuffer.resetAndAdjust(mSymbolTimingError);
if(mSamplesPerSymbolListener != null)
{
mSamplesPerSymbolListener.receive((double)mInterpolatingSymbolBuffer.getSamplingPoint());
}
//Store current samples/symbols to use for the next period
mPreviousPrecedingSample.setValues(mCurrentPrecedingSample);
mPreviousCurrentSample.setValues(mCurrentCurrentSample);
mPreviousFollowingSample.setValues(mCurrentFollowingSample);
//Calculate the phase error of the current symbol relative to the expected constellation and provide
//feedback to the PLL
mSymbolPhaseErrorCalculator.adjust(mCurrentSymbol);
mPhaseError = mSymbolPhaseErrorCalculator.getPhaseError(mCurrentSymbol);
mPhaseError = GardnerDetector.clip(mPhaseError, 0.15f);
mPLL.adjust(mPhaseError);
// mPLL.adjust(0.0);
if(mPLLErrorListener != null)
{
mPLLErrorListener.receive((double)mPhaseError);
}
if(mPLLFrequencyListener != null)
{
double loopFrequency = ((CostasLoop)mPLL).getLoopFrequency();
loopFrequency *= mSampleRate / (2.0 * Math.PI);
mPLLFrequencyListener.receive(loopFrequency);
}
//Decode the dibit from the symbol and send to the listener
if(mDibitListener != null)
{
mDibitListener.receive(mDQPSKSymbolDecoder.decode(mCurrentSymbol));
}
//TODO: Assemble dibits here and broadcast
calculateSymbol();
}
}
/**
* Registers the listener to receive decoded QPSK symbols
* Calculates a symbol from the interpolating buffer
*/
public void setSymbolListener(Listener<Complex> listener)
protected void calculateSymbol()
{
mSymbolListener = listener;
//Get preceding sample and an interpolated current sample from the interpolating buffer
mPrecedingSample = mInterpolatingSampleBuffer.getPrecedingSample();
mCurrentSample = mInterpolatingSampleBuffer.getCurrentSample();
//Calculate preceding, current and following symbols as the delta rotation compared to the previous samples
mPrecedingSymbol.setInphase(Complex.multiplyInphase(mPrecedingSample.inphase(), mPrecedingSample.quadrature(),
mPreviousPrecedingSample.inphase(), -mPreviousPrecedingSample.quadrature()));
mPrecedingSymbol.setQuadrature(Complex.multiplyQuadrature(mPrecedingSample.inphase(), mPrecedingSample.quadrature(),
mPreviousPrecedingSample.inphase(), -mPreviousPrecedingSample.quadrature()));
mCurrentSymbol.setInphase(Complex.multiplyInphase(mCurrentSample.inphase(), mCurrentSample.quadrature(),
mPreviousCurrentSample.inphase(), -mPreviousCurrentSample.quadrature()));
mCurrentSymbol.setQuadrature(Complex.multiplyQuadrature(mCurrentSample.inphase(), mCurrentSample.quadrature(),
mPreviousCurrentSample.inphase(), -mPreviousCurrentSample.quadrature()));
//Set gain to unity before we calculate the error value
mPrecedingSymbol.normalize();
mCurrentSymbol.normalize();
//Symbol timing error calculation
mSymbolTimingError = mDQPSKTimingErrorDetector.getError(mPrecedingSymbol, mCurrentSymbol);
mSymbolTimingError = clip(mSymbolTimingError, 0.5f);
mInterpolatingSampleBuffer.resetAndAdjust(mSymbolTimingError);
//Store current samples/symbols to use for the next period
mPreviousPrecedingSample.setValues(mPrecedingSample);
mPreviousCurrentSample.setValues(mCurrentSample);
//Calculate the phase error of the current symbol relative to the expected constellation and provide
//feedback to the PLL
mPhaseError = mSymbolPhaseErrorCalculator.getPhaseError(mCurrentSymbol);
mPLL.adjust(mPhaseError);
if(mDibitListener != null)
{
mDibitListener.receive(mDQPSKSymbolDecoder.decode(mCurrentSymbol));
}
}
/**
* Registers the listener to receive decoded QPSK dibits
* Registers the listener to receive dibit symbol decisions from this demodulator
*/
public void setDibitListener(Listener<Dibit> listener)
{
@@ -228,32 +158,19 @@ public class DQPSKDemodulator implements ComplexSampleListener
}
/**
* Registers the listener to receive PLL error values
* Constrains value to the range of ( -maximum <> maximum )
*/
public void setPLLErrorListener(Listener<Double> listener)
public static float clip(float value, float maximum)
{
mPLLErrorListener = listener;
}
if(value > maximum)
{
return maximum;
}
else if(value < -maximum)
{
return -maximum;
}
/**
* Registers the listener to receive PLL error values
*/
public void setPLLFrequencyListener(Listener<Double> listener)
{
mPLLFrequencyListener = listener;
return value;
}
/**
* Registers the listener to receive PLL error values
*/
public void setSamplesPerSymbolListener(Listener<Double> listener)
{
mSamplesPerSymbolListener = listener;
}
public void setSymbolDecisionDataListener(Listener<SymbolDecisionData2> listener)
{
mSymbolDecisionDataListener = listener;
}
}

134
src/main/java/io/github/dsheirer/dsp/psk/DQPSKDemodulatorInstrumented.java Normal file
View File

@@ -0,0 +1,134 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.dsp.psk.pll.CostasLoop;
import io.github.dsheirer.dsp.psk.pll.IPhaseLockedLoop;
import io.github.dsheirer.sample.Listener;
import io.github.dsheirer.sample.complex.Complex;
public class DQPSKDemodulatorInstrumented extends DQPSKDemodulator
{
private Listener<SymbolDecisionData> mSymbolDecisionDataListener;
private Listener<Double> mSamplesPerSymbolListener;
private Listener<Complex> mSymbolListener;
private Listener<Double> mPLLErrorListener;
private Listener<Double> mPLLFrequencyListener;
private double mSampleRate;
/**
* Decoder for Differential Quaternary Phase Shift Keying (DQPSK). This decoder uses both a Costas Loop (PLL) and
* a custom DQPSK symbol timing error detector to automatically align to the incoming carrier frequency and to
* adjust for any changes in symbol timing.
*
* This detector is optimized for constant amplitude DQPSK symbols like C4FM.
*
* @param phaseLockedLoop for tracking carrier frequency error
* @param symbolPhaseErrorCalculator to calculate symbol phase errors to apply against the PLL
* @param symbolDecoder to decode demodulated symbols into dibits
* @param interpolatingSampleBuffer
* @param sampleRate of the incoming complex sample stream
*/
public DQPSKDemodulatorInstrumented(IPhaseLockedLoop phaseLockedLoop, ISymbolPhaseErrorCalculator
symbolPhaseErrorCalculator, IQPSKSymbolDecoder symbolDecoder,
InterpolatingSampleBufferInstrumented interpolatingSampleBuffer,
double sampleRate)
{
super(phaseLockedLoop, symbolPhaseErrorCalculator, symbolDecoder, interpolatingSampleBuffer);
mSampleRate = sampleRate;
}
/**
* Overrides the parent class symbol calculation to capture eye diagram data
*/
protected void calculateSymbol()
{
//Eye diagram listener
if(mSymbolDecisionDataListener != null)
{
mSymbolDecisionDataListener.receive(
((InterpolatingSampleBufferInstrumented)mInterpolatingSampleBuffer).getSymbolDecisionData());
}
super.calculateSymbol();
if(mSamplesPerSymbolListener != null)
{
mSamplesPerSymbolListener.receive((double)mInterpolatingSampleBuffer.getSamplingPoint());
}
//Send to an external constellation symbol listener when registered
if(mSymbolListener != null)
{
mSymbolListener.receive(mCurrentSymbol);
}
if(mPLLErrorListener != null)
{
mPLLErrorListener.receive((double)mPhaseError);
}
if(mPLLFrequencyListener != null)
{
double loopFrequency = ((CostasLoop)mPLL).getLoopFrequency();
loopFrequency *= mSampleRate / (2.0 * Math.PI);
mPLLFrequencyListener.receive(loopFrequency);
}
}
/**
* Registers a listener to receive symbol decision data to produce an eye diagram.
*/
public void setSymbolDecisionDataListener(Listener<SymbolDecisionData> listener)
{
mSymbolDecisionDataListener = listener;
}
/**
* Registers the listener to receive PLL error values
*/
public void setSamplesPerSymbolListener(Listener<Double> listener)
{
mSamplesPerSymbolListener = listener;
}
/**
* Registers the listener to receive decoded QPSK symbols
*/
public void setSymbolListener(Listener<Complex> listener)
{
mSymbolListener = listener;
}
/**
* Registers the listener to receive PLL error values
*/
public void setPLLErrorListener(Listener<Double> listener)
{
mPLLErrorListener = listener;
}
/**
* Registers the listener to receive PLL error values
*/
public void setPLLFrequencyListener(Listener<Double> listener)
{
mPLLFrequencyListener = listener;
}
}

9
src/main/java/io/github/dsheirer/dsp/psk/DQPSKSymbolPhaseErrorCalculator.java
View File

@@ -21,16 +21,17 @@ public class DQPSKSymbolPhaseErrorCalculator extends QPSKSymbolPhaseErrorCalcula
{
//45 degrees rotation to orient the symbol to a polar axis to make error calculation easy/efficient
public static final Complex DIFFERENTIAL_OFFSET = Complex.fromAngle(Math.PI / 4.0d);
private boolean mToggle;
private Complex mSymbol = new Complex(0, 0);
public DQPSKSymbolPhaseErrorCalculator()
{
}
@Override
public void adjust(Complex symbol)
public float getPhaseError(Complex symbol)
{
symbol.multiply(DIFFERENTIAL_OFFSET);
mSymbol.setValues(symbol);
mSymbol.multiply(DIFFERENTIAL_OFFSET);
return super.getPhaseError(mSymbol);
}
}

89
src/main/java/io/github/dsheirer/dsp/psk/DQPSKTimingErrorDetector.java Normal file
View File

@@ -0,0 +1,89 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.sample.complex.Complex;
public class DQPSKTimingErrorDetector
{
private static final float PI_4_ROTATION = (float)(Math.PI / 4.0);
/**
* Custom early/late symbol timing error detector designed to optimize the sample timing point such that the
* current symbol's inphase and quadrature approach the optimal 45 degree (.707) sampling instant.
*/
public DQPSKTimingErrorDetector()
{
}
/**
* Calculates a symbol sampling time error by comparing the current complex sample against a normal QPSK or
* Pi/4 rotated four symbol constellation. The error signal (advance/retard) is determined by the slope
* of each of the inphase and quadrature legs as detected by comparing an immediately preceding sample against
* the current sample and then calculating the error distance of the sampled symbol from the ideal Pi/4 sampling
* location.
*
* Note: both the preceding and the current symbols MUST be normalized (ie symbol.normalize()) to the unit circle
* prior to invoking this method.
*
* @param precedingSymbol
* @param currentSymbol
* @return timing error signal used to advance (positive) or retard (negative) the sampling point
*/
public float getError(Complex precedingSymbol, Complex currentSymbol)
{
return getError(precedingSymbol.inphase(), currentSymbol.inphase()) +
getError(precedingSymbol.quadrature(), currentSymbol.quadrature());
}
/**
* Calculates timing error of current value relative to an ideal 45 degree or Pi/4 radians (.707) value.
*
* @param early sample that closely precedes the current sampling instant - used to determine slope
* @param current sampling value
* @return error as the distance of the current value from an ideal value and the sign (advance/retard)
* appropriate for the detected slope
*/
private float getError(float early, float current)
{
if(early < current) //Ascending slope
{
if(current > 0.0)
{
//Positive quadrature hemisphere, ascending slope
return PI_4_ROTATION - current;
}
else
{
//Negative quadrature hemisphere, ascending slope
return -PI_4_ROTATION - current;
}
}
else //Descending slope
{
if(current > 0.0)
{
//Positive quadrature hemisphere, descending slope
return current - PI_4_ROTATION;
}
else
{
//Negative quadrature hemisphere, descending slope
return current + PI_4_ROTATION;
}
}
}
}

76
src/main/java/io/github/dsheirer/dsp/psk/EarlyLateDetector.java
View File

@@ -1,76 +0,0 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.sample.complex.Complex;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class EarlyLateDetector
{
private static final float PI_4_ROTATION = (float)(Math.PI / 4.0);
private final static Logger mLog = LoggerFactory.getLogger(EarlyLateDetector.class);
/**
* Symbol timing error detector designed to optimize the sample timing point such that the current symbol's
* inphase and quadrature approach the optimal 45 degree (.707) sampling instant.
*/
public EarlyLateDetector()
{
}
public float getError(Complex early, Complex current, Complex late)
{
float inphaseError = getError(early.inphase(), current.inphase(), late.inphase());
float quadratureError = getError(early.quadrature(), current.quadrature(), late.quadrature());
float error = inphaseError + quadratureError;
mLog.debug("I:" + inphaseError + " Q:" + quadratureError + " E:" + error);
return error;
// return getError(early.inphase(), current.inphase(), late.inphase()) -
// getError(early.quadrature(), current.quadrature(), late.quadrature());
}
private float getError(float early, float current, float late)
{
if(early < current) //Ascending slope
{
if(current > 0.0)
{
//Positive hemisphere, ascending slope
return PI_4_ROTATION - current;
}
else
{
//Negative hemisphere, ascending slope
return -PI_4_ROTATION - current;
}
}
else //Descending slope
{
if(current > 0.0)
{
//Positive hemisphere, descending slope
return current - PI_4_ROTATION;
}
else
{
//Negative hemisphere, descending slope
return current + PI_4_ROTATION;
}
}
}
}

7
src/main/java/io/github/dsheirer/dsp/psk/ISymbolPhaseErrorCalculator.java
View File

@@ -19,13 +19,6 @@ import io.github.dsheirer.sample.complex.Complex;
public interface ISymbolPhaseErrorCalculator
{
/**
* Adjusts the calculated symbol as necessary before calculating any phase error. This might be useful for
* differential encoding to remove a 45 degree rotational spin.
* @param symbol to adjust
*/
void adjust(Complex symbol);
/**
* Calculates the phase error of the symbol relative to an alignment for the constellation
* @param symbol to calculate error

164
src/main/java/io/github/dsheirer/dsp/psk/InterpolatingSymbolBuffer2.java → src/main/java/io/github/dsheirer/dsp/psk/InterpolatingSampleBuffer.java
View File

@@ -17,59 +17,60 @@ package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.dsp.filter.interpolator.RealInterpolator;
import io.github.dsheirer.sample.complex.Complex;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class InterpolatingSymbolBuffer2
public class InterpolatingSampleBuffer
{
private static final float MAXIMUM_SAMPLES_PER_SYMBOL_DEVIATION = 0.02f; //2%
private final static Logger mLog = LoggerFactory.getLogger(InterpolatingSymbolBuffer2.class);
private Complex mPreceedingSample = new Complex(0,0);
private static final float MAXIMUM_DEVIATION_SAMPLES_PER_SYMBOL = 0.02f; // +/- 2% deviation
private Complex mPrecedingSample = new Complex(0,0);
private Complex mCurrentSample = new Complex(0,0);
private Complex mFollowingSample = new Complex(0,0);
private float[] mDelayLineInphase;
private float[] mDelayLineQuadrature;
private int mDelayLinePointer = 0;
private int mTwiceSamplesPerSymbol;
private float mSamplingPoint;
private float mSampleCounterGain = 0.05f;
private float mDetectedSamplesPerSymbol;
private float mDetectedSamplesPerSymbolGain = 0.1f * mSampleCounterGain * mSampleCounterGain;
private float mMaximumSamplesPerSymbol;;
private float mMinimumSamplesPerSymbol;;
private float mMaximumSamplesPerSymbol;
private float mMinimumSamplesPerSymbol;
private int mDelayLinePointer = 0;
private int mTwiceSamplesPerSymbol;
private RealInterpolator mInterpolator = new RealInterpolator(1.0f);
private SymbolDecisionData2 mSymbolDecisionData2;
public InterpolatingSymbolBuffer2(float samplesPerSymbol)
/**
* Buffer to store complex sample data and produce interpolated samples.
* @param samplesPerSymbol
*/
public InterpolatingSampleBuffer(float samplesPerSymbol)
{
mSamplingPoint = samplesPerSymbol;
mDetectedSamplesPerSymbol = samplesPerSymbol;
mMaximumSamplesPerSymbol = samplesPerSymbol * (1.0f + MAXIMUM_SAMPLES_PER_SYMBOL_DEVIATION);
mMinimumSamplesPerSymbol = samplesPerSymbol * (1.0f - MAXIMUM_SAMPLES_PER_SYMBOL_DEVIATION);
mMaximumSamplesPerSymbol = samplesPerSymbol * (1.0f + MAXIMUM_DEVIATION_SAMPLES_PER_SYMBOL);
mMinimumSamplesPerSymbol = samplesPerSymbol * (1.0f - MAXIMUM_DEVIATION_SAMPLES_PER_SYMBOL);
mTwiceSamplesPerSymbol = (int)Math.floor(2.0 * samplesPerSymbol);
mDelayLineInphase = new float[2 * mTwiceSamplesPerSymbol];
mDelayLineQuadrature = new float[2 * mTwiceSamplesPerSymbol];
mSymbolDecisionData2 = new SymbolDecisionData2((int)samplesPerSymbol);
}
public void receive(Complex currentSample)
/**
* Stores the sample in the buffer and updates pointers.
* @param sample
*/
public void receive(Complex sample)
{
mSymbolDecisionData2.receive(currentSample);
mSamplingPoint--;
//Fill up the delay line to use with the interpolator
mDelayLineInphase[mDelayLinePointer] = currentSample.inphase();
mDelayLineInphase[mDelayLinePointer + mTwiceSamplesPerSymbol] = currentSample.inphase();
mDelayLineQuadrature[mDelayLinePointer] = currentSample.quadrature();
mDelayLineQuadrature[mDelayLinePointer + mTwiceSamplesPerSymbol] = currentSample.quadrature();
mDelayLineInphase[mDelayLinePointer] = sample.inphase();
mDelayLineInphase[mDelayLinePointer + mTwiceSamplesPerSymbol] = sample.inphase();
mDelayLineQuadrature[mDelayLinePointer] = sample.quadrature();
mDelayLineQuadrature[mDelayLinePointer + mTwiceSamplesPerSymbol] = sample.quadrature();
//Increment pointer and keep pointer in bounds
mDelayLinePointer++;
mDelayLinePointer = mDelayLinePointer % mTwiceSamplesPerSymbol;
}
/**
@@ -89,15 +90,22 @@ public class InterpolatingSymbolBuffer2
*/
public void resetAndAdjust(float symbolTimingError)
{
//mDetectedSamplesPerSymbol is samples per symbol and is constrained to floating between +/- .005 of the nominal samples per
//symbol
//Adjust detected samples per symbol based on timing error
mDetectedSamplesPerSymbol = mDetectedSamplesPerSymbol + (symbolTimingError * mDetectedSamplesPerSymbolGain);
mDetectedSamplesPerSymbol = constrain(mDetectedSamplesPerSymbol, mMinimumSamplesPerSymbol, mMaximumSamplesPerSymbol);
mLog.debug("Detected Samples Per Symbol: " + mDetectedSamplesPerSymbol);
//Constrain detected samples per symbol to min/max values
if(mDetectedSamplesPerSymbol > mMaximumSamplesPerSymbol)
{
mDetectedSamplesPerSymbol = mMaximumSamplesPerSymbol;
}
if(mDetectedSamplesPerSymbol < mMinimumSamplesPerSymbol)
{
mDetectedSamplesPerSymbol = mMinimumSamplesPerSymbol;
}
//Add another symbol's worth of samples to the counter and adjust timing based on gardner error
increaseSampleCounter((mDetectedSamplesPerSymbol + (mSampleCounterGain * symbolTimingError)));
// increaseSampleCounter(mDetectedSamplesPerSymbol);
increaseSampleCounter((mDetectedSamplesPerSymbol + (symbolTimingError * mSampleCounterGain)));
}
/**
@@ -117,13 +125,13 @@ public class InterpolatingSymbolBuffer2
}
/**
* Samples that precedes the current sample (uninterpolated).
* Un-interpolated sample that precedes the current interpolated sampling point. The current sampling point falls
* somewhere between sample index 3 and index 4, therefore the preceding sample is located at index 3.
*/
public Complex getPreceedingSample()
public Complex getPrecedingSample()
{
mPreceedingSample.setValues(mDelayLineInphase[mDelayLinePointer + 3], mDelayLineQuadrature[mDelayLinePointer + 3]);
return mPreceedingSample;
mPrecedingSample.setValues(mDelayLineInphase[mDelayLinePointer + 3], mDelayLineQuadrature[mDelayLinePointer + 3]);
return mPrecedingSample;
}
/**
@@ -134,33 +142,9 @@ public class InterpolatingSymbolBuffer2
{
/* Calculate interpolated current sample */
mCurrentSample.setValues(getInphase(mSamplingPoint), getQuadrature(mSamplingPoint));
return mCurrentSample;
}
/**
* Samples that follows the current sample (uninterpolated).
*/
public Complex getFollowingSample()
{
mFollowingSample.setValues(mDelayLineInphase[mDelayLinePointer + 4], mDelayLineQuadrature[mDelayLinePointer + 4]);
return mFollowingSample;
}
/**
* Contents of the interpolating buffer and the current buffer index and symbol decision offset. This data can
* be used to support an external eye-diagram chart.
* @return symbol decision data.
*/
public SymbolDecisionData2 getSymbolDecisionData()
{
mSymbolDecisionData2.setSamplingPoint(mSamplingPoint);
return mSymbolDecisionData2;
}
/**
* Returns the interpolated inphase value for the specified offset
* @param interpolation into the buffer to calculate the interpolated sample
@@ -171,17 +155,6 @@ public class InterpolatingSymbolBuffer2
return mInterpolator.filter(mDelayLineInphase, mDelayLinePointer, interpolation);
}
/**
* Returns the interpolated inphase value for the specified offset
* @param delayLineOffset offset into the inphase delay line buffer
* @param interpolation into the buffer to calculate the interpolated sample
* @return inphase value of the interpolated sample
*/
public float getInphase(int delayLineOffset, float interpolation)
{
return mInterpolator.filter(mDelayLineInphase, mDelayLinePointer + delayLineOffset, interpolation);
}
/**
* Returns the interpolated quadrature value for the specified offset
* @param interpolation into the buffer to calculate the interpolated sample
@@ -191,55 +164,4 @@ public class InterpolatingSymbolBuffer2
{
return mInterpolator.filter(mDelayLineQuadrature, mDelayLinePointer, interpolation);
}
/**
* Returns the interpolated quadrature value for the specified offset
* @param delayLineOffset offset into the quadrature delay line buffer
* @param interpolation into the buffer to calculate the interpolated sample
* @return quadrature value of the interpolated sample
*/
public float getQuadrature(int delayLineOffset, float interpolation)
{
return mInterpolator.filter(mDelayLineQuadrature, mDelayLinePointer + delayLineOffset, interpolation);
}
/**
* Constrains value to the range of ( -maximum <> maximum )
*/
public static float clip(float value, float maximum)
{
if(value > maximum)
{
return maximum;
}
else if(value < -maximum)
{
return -maximum;
}
return value;
}
/**
* Constrains the value within the minimum-maximum range
*
* @param value to constrain
* @param minimum value
* @param maximum value
* @return constrained value
*/
public static float constrain(float value, float minimum, float maximum)
{
if(value > maximum)
{
return maximum;
}
if(value < minimum)
{
return minimum;
}
return value;
}
}

38
src/main/java/io/github/dsheirer/dsp/psk/EarlyLateDetector2.java → src/main/java/io/github/dsheirer/dsp/psk/InterpolatingSampleBufferInstrumented.java
View File

@@ -17,24 +17,32 @@ package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.sample.complex.Complex;
public class EarlyLateDetector2
public class InterpolatingSampleBufferInstrumented extends InterpolatingSampleBuffer
{
//45 degrees rotation to orient the symbol to a polar axis to make error calculation easy/efficient
public static final Complex POSITIVE_OFFSET = Complex.fromAngle(Math.PI / 4.0d);
private Complex mSymbol = new Complex(0,0);
private SymbolDecisionData mSymbolDecisionData;
public float getError(Complex symbol)
public InterpolatingSampleBufferInstrumented(float samplesPerSymbol)
{
mSymbol.setValues(symbol);
mSymbol.multiply(POSITIVE_OFFSET);
super(samplesPerSymbol);
if(Math.abs(mSymbol.quadrature()) > Math.abs(mSymbol.inphase()))
{
return mSymbol.inphase();
}
else
{
return mSymbol.quadrature();
}
mSymbolDecisionData = new SymbolDecisionData((int)samplesPerSymbol);
}
public void receive(Complex sample)
{
super.receive(sample);
mSymbolDecisionData.receive(sample);
}
/**
* Contents of the interpolating buffer and the current buffer index and symbol decision offset. This data can
* be used to support an external eye-diagram chart.
* @return symbol decision data.
*/
public SymbolDecisionData getSymbolDecisionData()
{
mSymbolDecisionData.setSamplingPoint(getSamplingPoint());
return mSymbolDecisionData;
}
}

219
src/main/java/io/github/dsheirer/dsp/psk/InterpolatingSymbolBuffer.java
View File

@@ -1,219 +0,0 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.dsp.filter.interpolator.RealInterpolator;
import io.github.dsheirer.sample.complex.Complex;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class InterpolatingSymbolBuffer
{
private final static Logger mLog = LoggerFactory.getLogger(InterpolatingSymbolBuffer.class);
private Complex mMiddleSample = new Complex(0,0);
private Complex mCurrentSample = new Complex(0,0);
private float[] mDelayLineInphase;
private float[] mDelayLineQuadrature;
private float mSamplingPoint; //Sample Counter
private float mSampleCounterGain = 0.05f; //Sample Counter Gain
private float mSamplesPerSymbol;
private float mDetectedSamplesPerSymbol;
private float mDetectedSamplesPerSymbolGain = 0.1f * mSampleCounterGain * mSampleCounterGain;
private float mMaxDeviation = 0.005f;
private int mDelayLinePointer = 0;
private int mTwiceSamplesPerSymbol;
private RealInterpolator mInterpolator = new RealInterpolator(1.0f);
private SymbolDecisionData2 mSymbolDecisionData2;
public InterpolatingSymbolBuffer(float samplesPerSymbol)
{
mSamplingPoint = samplesPerSymbol;
mTwiceSamplesPerSymbol = (int)Math.floor(2.0 * samplesPerSymbol);
mDelayLineInphase = new float[2 * mTwiceSamplesPerSymbol];
mDelayLineQuadrature = new float[2 * mTwiceSamplesPerSymbol];
mDetectedSamplesPerSymbol = samplesPerSymbol;
mSamplesPerSymbol = samplesPerSymbol;
mSymbolDecisionData2 = new SymbolDecisionData2((int)samplesPerSymbol);
}
public void receive(Complex currentSample)
{
mSymbolDecisionData2.receive(currentSample);
mSamplingPoint--;
//Fill up the delay line to use with the interpolator
mDelayLineInphase[mDelayLinePointer] = currentSample.inphase();
mDelayLineInphase[mDelayLinePointer + mTwiceSamplesPerSymbol] = currentSample.inphase();
mDelayLineQuadrature[mDelayLinePointer] = currentSample.quadrature();
mDelayLineQuadrature[mDelayLinePointer + mTwiceSamplesPerSymbol] = currentSample.quadrature();
//Increment pointer and keep pointer in bounds
mDelayLinePointer++;
mDelayLinePointer = mDelayLinePointer % mTwiceSamplesPerSymbol;
}
/**
* Updates the internal sample counter with additional samples to add to the symbol sample counter.
* @param samplesToAdd to the sample counter
*/
public void increaseSampleCounter(float samplesToAdd)
{
mSamplingPoint += samplesToAdd;
}
/**
* Adjusts samples per symbol and symbol timing counters and increments the sample counter to collect another
* symbol.
*
* @param symbolTimingError from a symbol timing error detector
*/
public void resetAndAdjust(float symbolTimingError)
{
//mDetectedSamplesPerSymbol is samples per symbol and is constrained to floating between +/- .005 of the nominal samples per
//symbol
mDetectedSamplesPerSymbol = mDetectedSamplesPerSymbol + mDetectedSamplesPerSymbolGain * symbolTimingError;
mDetectedSamplesPerSymbol = mSamplesPerSymbol + clip(mDetectedSamplesPerSymbol - mSamplesPerSymbol, mMaxDeviation);
mLog.debug("Detected Samples Per Symbol:" + mDetectedSamplesPerSymbol);
//Add another symbol's worth of samples to the counter and adjust timing based on gardner error
increaseSampleCounter((mDetectedSamplesPerSymbol + (mSampleCounterGain * symbolTimingError)));
}
/**
* Current value of the detected samples per symbol
*/
public float getSamplingPoint()
{
return mSamplingPoint;
}
/**
* Indicates if this buffer has accumulated a enough samples to represent a full symbol
*/
public boolean hasSymbol()
{
return mSamplingPoint < 1.0f;
}
/**
* Interpolated middle sample for the symbol. Note: this method should only be invoked after testing for a
* complete symbol with the hasSymbol() method.
*/
public Complex getMiddleSample()
{
/* Calculate interpolated middle sample and current sample */
mMiddleSample.setValues(getInphase(mSamplingPoint), getQuadrature(mSamplingPoint));
return mMiddleSample;
}
/**
* Interpolated current sample for the symbol. This sample represents the ideal symbol sampling point.
* Note: this method should only be invoked after testing for a complete symbol with the hasSymbol() method.
*/
public Complex getCurrentSample()
{
float halfDetectedSamplesPerSymbol = mDetectedSamplesPerSymbol / 2.0f;
int halfSamplingPointOffset = (int)Math.floor(halfDetectedSamplesPerSymbol);
float halfSamplingPoint = mSamplingPoint + halfDetectedSamplesPerSymbol - halfSamplingPointOffset;
if(halfSamplingPoint > 1.0)
{
halfSamplingPoint -= 1.0;
halfSamplingPointOffset += 1;
}
mCurrentSample.setValues(getInphase(halfSamplingPointOffset, halfSamplingPoint),
getQuadrature(halfSamplingPointOffset, halfSamplingPoint));
return mCurrentSample;
}
/**
* Contents of the interpolating buffer and the current buffer index and symbol decision offset. This data can
* be used to support an external eye-diagram chart.
* @return symbol decision data.
*/
public SymbolDecisionData2 getSymbolDecisionData()
{
mSymbolDecisionData2.setSamplingPoint(mSamplingPoint);
return mSymbolDecisionData2;
}
/**
* Returns the interpolated inphase value for the specified offset
* @param interpolation into the buffer to calculate the interpolated sample
* @return inphase value of the interpolated sample
*/
public float getInphase(float interpolation)
{
return mInterpolator.filter(mDelayLineInphase, mDelayLinePointer, interpolation);
}
/**
* Returns the interpolated inphase value for the specified offset
* @param delayLineOffset offset into the inphase delay line buffer
* @param interpolation into the buffer to calculate the interpolated sample
* @return inphase value of the interpolated sample
*/
public float getInphase(int delayLineOffset, float interpolation)
{
return mInterpolator.filter(mDelayLineInphase, mDelayLinePointer + delayLineOffset, interpolation);
}
/**
* Returns the interpolated quadrature value for the specified offset
* @param interpolation into the buffer to calculate the interpolated sample
* @return quadrature value of the interpolated sample
*/
public float getQuadrature(float interpolation)
{
return mInterpolator.filter(mDelayLineQuadrature, mDelayLinePointer, interpolation);
}
/**
* Returns the interpolated quadrature value for the specified offset
* @param delayLineOffset offset into the quadrature delay line buffer
* @param interpolation into the buffer to calculate the interpolated sample
* @return quadrature value of the interpolated sample
*/
public float getQuadrature(int delayLineOffset, float interpolation)
{
return mInterpolator.filter(mDelayLineQuadrature, mDelayLinePointer + delayLineOffset, interpolation);
}
/**
* Constrains value to the range of ( -maximum <> maximum )
*/
public static float clip(float value, float maximum)
{
if(value > maximum)
{
return maximum;
}
else if(value < -maximum)
{
return -maximum;
}
return value;
}
}

7
src/main/java/io/github/dsheirer/dsp/psk/LSMDemodulator.java
View File

@@ -449,6 +449,13 @@ public class LSMDemodulator implements Instrumentable, ComplexSampleListener
unwrapPhase();
}
@Override
public void reset()
{
mLoopPhase = 0.0f;
mLoopFrequency = 0.0f;
}
@Override
public void adjust(double error)
{

233
src/main/java/io/github/dsheirer/dsp/psk/QPSKDemodulator.java
View File

@@ -1,233 +0,0 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.dsp.psk.pll.CostasLoop;
import io.github.dsheirer.dsp.psk.pll.IPhaseLockedLoop;
import io.github.dsheirer.dsp.symbol.Dibit;
import io.github.dsheirer.sample.Listener;
import io.github.dsheirer.sample.complex.Complex;
import io.github.dsheirer.sample.complex.ComplexBuffer;
import io.github.dsheirer.sample.complex.ComplexSampleListener;
public class QPSKDemodulator implements ComplexSampleListener
{
private InterpolatingSymbolBuffer mInterpolatingSymbolBuffer;
private IPhaseLockedLoop mPLL;
private ISymbolPhaseErrorCalculator mSymbolPhaseErrorCalculator;
private IQPSKSymbolDecoder mQPSKSymbolDecoder;
private GardnerDetector mGardnerDetector = new GardnerDetector();
private Listener<Complex> mSymbolListener;
private Listener<Double> mPLLErrorListener;
private Listener<Double> mPLLFrequencyListener;
private Listener<Double> mSamplesPerSymbolListener;
private Listener<Dibit> mDibitListener;
private Listener<SymbolDecisionData2> mSymbolDecisionDataListener;
private Complex mPreviousSample = new Complex(0, 0);
private Complex mPreviousMiddleSample = new Complex(0, 0);
private Complex mCurrentSample = new Complex(0, 0);
private Complex mMiddleSample = new Complex(0, 0);
private Complex mPreviousSymbol = new Complex(0, 0);
private Complex mMiddleSymbol = new Complex(0, 0);
private Complex mCurrentSymbol = new Complex(0, 0);
private float mPhaseError;
private float mSymbolTimingError;
private double mSampleRate;
/**
* Decoder for Quaternary Phase Shift Keying (QPSK) and Differential QPSK (DQPSK). This decoder uses both a
* phase-locked loop and a gardner symbol timing error detector to automatically align to the incoming carrier
* frequency and to adjust for any changes in symbol timing.
*
* @param phaseLockedLoop for tracking carrier frequency error
* @param symbolPhaseErrorCalculator to calculate symbol phase errors and optionally adjust for differential encoding
* @param symbolDecoder to decode demodulated symbols into dibits
* @param sampleRate of the incoming complex sample stream
* @param symbolRate of the decoded QPSK symbols.
*/
public QPSKDemodulator(IPhaseLockedLoop phaseLockedLoop, ISymbolPhaseErrorCalculator symbolPhaseErrorCalculator,
IQPSKSymbolDecoder symbolDecoder, double sampleRate, double symbolRate)
{
if(sampleRate < (symbolRate * 2))
{
throw new IllegalArgumentException("Sample rate [" + sampleRate +
"] must be at least 2 x symbol rate [" + symbolRate + "]");
}
mSampleRate = sampleRate;
mPLL = phaseLockedLoop;
mSymbolPhaseErrorCalculator = symbolPhaseErrorCalculator;
mQPSKSymbolDecoder = symbolDecoder;
float samplesPerSymbol = (float)(sampleRate / symbolRate);
mInterpolatingSymbolBuffer = new InterpolatingSymbolBuffer(samplesPerSymbol);
}
/**
* Submits a buffer containing complex samples for decoding
* @param complexBuffer with complex samples
*/
public void receive(ComplexBuffer complexBuffer)
{
float[] samples = complexBuffer.getSamples();
for(int x = 0; x < samples.length; x += 2)
{
receive(samples[x], samples[x + 1]);
}
}
/**
* Submits a complex sample for decoding.
* @param inphase value for the sample
* @param quadrature value for the sample
*/
@Override
public void receive(float inphase, float quadrature)
{
//Update current sample with values
mCurrentSample.setValues(inphase, quadrature);
//Mix current sample with costas loop to remove any rotation that is present from a mis-tuned carrier frequency
mCurrentSample.multiply(mPLL.incrementAndGetCurrentVector());
mInterpolatingSymbolBuffer.receive(mCurrentSample);
//Calculate the symbol once we've stored enough samples
if(mInterpolatingSymbolBuffer.hasSymbol())
{
//Get middle and current samples from the interpolating buffer
mMiddleSample = mInterpolatingSymbolBuffer.getMiddleSample();
mCurrentSample = mInterpolatingSymbolBuffer.getCurrentSample();
//Eye diagram listener
if(mSymbolDecisionDataListener != null)
{
mSymbolDecisionDataListener.receive(mInterpolatingSymbolBuffer.getSymbolDecisionData());
}
//Calculate middle and current symbols as the delta between the previous and current samples
mMiddleSymbol.setInphase(Complex.multiplyInphase(mMiddleSample.inphase(), mMiddleSample.quadrature(), mPreviousMiddleSample.inphase(), -mPreviousMiddleSample.quadrature()));
mMiddleSymbol.setQuadrature(Complex.multiplyQuadrature(mMiddleSample.inphase(), mMiddleSample.quadrature(), mPreviousMiddleSample.inphase(), -mPreviousMiddleSample.quadrature()));
mCurrentSymbol.setInphase(Complex.multiplyInphase(mCurrentSample.inphase(), mCurrentSample.quadrature(), mPreviousSample.inphase(), -mPreviousSample.quadrature()));
mCurrentSymbol.setQuadrature(Complex.multiplyQuadrature(mCurrentSample.inphase(), mCurrentSample.quadrature(), mPreviousSample.inphase(), -mPreviousSample.quadrature()));
//Set gain to unity before we calculate the error value
mMiddleSymbol.normalize();
mCurrentSymbol.normalize();
//Send to an external constellation symbol listener when registered
if(mSymbolListener != null)
{
mSymbolListener.receive(mCurrentSymbol);
}
//Symbol timing error calculations
mSymbolTimingError = mGardnerDetector.getError(mPreviousSymbol, mMiddleSymbol, mCurrentSymbol);
mInterpolatingSymbolBuffer.resetAndAdjust(mSymbolTimingError);
if(mSamplesPerSymbolListener != null)
{
mSamplesPerSymbolListener.receive((double)mInterpolatingSymbolBuffer.getSamplingPoint());
}
//Store current samples/symbols to use for the next period
mPreviousSample.setValues(mCurrentSample);
mPreviousMiddleSample.setValues(mMiddleSample);
mPreviousSymbol.setValues(mCurrentSymbol);
//Calculate the phase error of the current symbol relative to the expected constellation and provide
//feedback to the PLL
mSymbolPhaseErrorCalculator.adjust(mCurrentSymbol);
mPhaseError = mSymbolPhaseErrorCalculator.getPhaseError(mCurrentSymbol);
mPhaseError = GardnerDetector.clip(mPhaseError, 0.15f);
// mPLL.adjust(-mPhaseError);
mPLL.adjust(0.0);
if(mPLLErrorListener != null)
{
mPLLErrorListener.receive((double)mPhaseError);
}
if(mPLLFrequencyListener != null)
{
double loopFrequency = ((CostasLoop)mPLL).getLoopFrequency();
loopFrequency *= mSampleRate / (2.0 * Math.PI);
mPLLFrequencyListener.receive(loopFrequency);
}
//Decode the dibit from the symbol and send to the listener
if(mDibitListener != null)
{
mDibitListener.receive(mQPSKSymbolDecoder.decode(mCurrentSymbol));
}
//TODO: Assemble dibits here and broadcast
}
}
/**
* Registers the listener to receive decoded QPSK symbols
*/
public void setSymbolListener(Listener<Complex> listener)
{
mSymbolListener = listener;
}
/**
* Registers the listener to receive decoded QPSK dibits
*/
public void setDibitListener(Listener<Dibit> listener)
{
mDibitListener = listener;
}
/**
* Registers the listener to receive PLL error values
*/
public void setPLLErrorListener(Listener<Double> listener)
{
mPLLErrorListener = listener;
}
/**
* Registers the listener to receive PLL error values
*/
public void setPLLFrequencyListener(Listener<Double> listener)
{
mPLLFrequencyListener = listener;
}
/**
* Registers the listener to receive PLL error values
*/
public void setSamplesPerSymbolListener(Listener<Double> listener)
{
mSamplesPerSymbolListener = listener;
}
public void setSymbolDecisionDataListener(Listener<SymbolDecisionData2> listener)
{
mSymbolDecisionDataListener = listener;
}
}

6
src/main/java/io/github/dsheirer/dsp/psk/QPSKSymbolPhaseErrorCalculator.java
View File

@@ -24,12 +24,6 @@ public class QPSKSymbolPhaseErrorCalculator implements ISymbolPhaseErrorCalculat
{
private float mPhaseError;
@Override
public void adjust(Complex symbol)
{
//No-op - since there is no differential, we don't have to adjust
}
@Override
public float getPhaseError(Complex symbol)
{

81
src/main/java/io/github/dsheirer/dsp/psk/SymbolDecisionData.java
View File

@@ -15,56 +15,79 @@
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.buffer.ComplexCircularBuffer;
import io.github.dsheirer.sample.complex.Complex;
public class SymbolDecisionData
{
private float[] mSamplesInphase;
private float[] mSamplesQuadrature;
private float mSamplesPerSymbol;
private int mSampleIndex;
private float mSampleIndexOffset;
//45 degrees rotation to orient the symbol to a polar axis to make error calculation easy/efficient
public static final Complex DIFFERENTIAL_OFFSET = Complex.fromAngle(Math.PI / 4.0d);
private ComplexCircularBuffer mBuffer;
private float mSamplingPoint;
/**
* Symbol decision data - samples and timing decision for a single symbol decision instant.
*
* @param samplesInphase
* @param samplesQuadrature
* @param samplesPerSymbol
* @param sampleIndex
* @param sampleIndexOffset
* Circular buffer for capturing two symbols worth of sample data for use in instrumentation.
* @param samplesPerSymbol to size the buffer
*/
public SymbolDecisionData(float[] samplesInphase, float[] samplesQuadrature, float samplesPerSymbol,
int sampleIndex, float sampleIndexOffset)
public SymbolDecisionData(int samplesPerSymbol)
{
mSamplesInphase = samplesInphase;
mSamplesQuadrature = samplesQuadrature;
mSamplesPerSymbol = samplesPerSymbol;
mSampleIndex = sampleIndex;
mSampleIndexOffset = sampleIndexOffset;
mBuffer = new ComplexCircularBuffer(2 * samplesPerSymbol);
}
public float[] getInphaseSamples()
/**
* Stores the complex sample in the buffer
*/
public void receive(float inphase, float quadrature)
{
return mSamplesInphase;
mBuffer.put(new Complex(inphase, quadrature));
}
public float[] getQuadratureSamples()
/**
* Stores the complex sample in the buffer
*/
public void receive(Complex complex)
{
return mSamplesQuadrature;
mBuffer.put(complex.copy());
}
public float getSamplesPerSymbol()
/**
* Sets the fractional sampling point for the current symbol to use in interpolating the current symbol.
*/
public void setSamplingPoint(float samplingPoint)
{
return mSamplesPerSymbol;
mSamplingPoint = samplingPoint;
}
public int getSampleIndex()
/**
* Fractional sampling point
*/
public float getSamplingPoint()
{
return mSampleIndex;
return mSamplingPoint;
}
public float getSampleIndexOffset()
/**
* Array of demodulated samples representing the current symbol where each current sample is demodulated against
* the previous symbol's sample to produce the differential demodulated sample. Samples are in time order.
*
* Note: differential decoding is on an integral samples-per-symbol basis and does not use fractional interpolation.
*/
public Complex[] getDemodulated()
{
return mSampleIndexOffset;
Complex[] samples = mBuffer.getAll();
int length = samples.length / 2;
Complex[] demodulated = new Complex[length];
for(int x = 0; x < samples.length / 2; x++)
{
Complex copy = samples[length + x].copy();
copy.multiply(samples[x].conjugate());
demodulated[x] = copy;
}
return demodulated;
}
}

74
src/main/java/io/github/dsheirer/dsp/psk/SymbolDecisionData2.java
View File

@@ -1,74 +0,0 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.dsp.psk;
import io.github.dsheirer.buffer.ComplexCircularBuffer;
import io.github.dsheirer.sample.complex.Complex;
public class SymbolDecisionData2
{
//45 degrees rotation to orient the symbol to a polar axis to make error calculation easy/efficient
public static final Complex DIFFERENTIAL_OFFSET = Complex.fromAngle(Math.PI / 4.0d);
private ComplexCircularBuffer mBuffer;
private float mSamplingPoint;
public SymbolDecisionData2(int samplesPerSymbol)
{
mBuffer = new ComplexCircularBuffer(2 * samplesPerSymbol);
}
public void receive(float inphase, float quadrature)
{
mBuffer.put(new Complex(inphase, quadrature));
}
public void receive(Complex complex)
{
mBuffer.put(complex.copy());
}
public void setSamplingPoint(float samplingPoint)
{
mSamplingPoint = samplingPoint;
}
public float getSamplingPoint()
{
return mSamplingPoint;
}
public Complex[] getDemodulated()
{
Complex[] samples = mBuffer.getAll();
int length = samples.length / 2;
Complex[] demodulated = new Complex[length];
for(int x = 0; x < samples.length / 2; x++)
{
Complex copy = samples[length + x].copy();
copy.multiply(samples[x].conjugate());
//Test - rotate the demodulated symbol by 45 degrees to see the impact on the eye diagram
// copy.multiply(DIFFERENTIAL_OFFSET);
demodulated[x] = copy;
}
return demodulated;
}
}

215
src/main/java/io/github/dsheirer/dsp/psk/pll/CostasLoop.java
View File

@@ -15,13 +15,7 @@
******************************************************************************/
package io.github.dsheirer.dsp.psk.pll;
import io.github.dsheirer.buffer.DoubleCircularBuffer;
import io.github.dsheirer.dsp.mixer.Oscillator;
import io.github.dsheirer.sample.complex.Complex;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.text.DecimalFormat;
/**
* Costas Loop - phase locked loop designed to automatically synchronize to the incoming carrier frequency in order to
@@ -34,21 +28,16 @@ import java.text.DecimalFormat;
*/
public class CostasLoop implements IPhaseLockedLoop
{
private final static Logger mLog = LoggerFactory.getLogger(CostasLoop.class);
public static final double TWO_PI = 2.0 * Math.PI;
private DoubleCircularBuffer mErrorBuffer = new DoubleCircularBuffer(10);
private Complex mCurrentVector = new Complex(0, 0);
private double mLoopPhase = 0.0;
private double mLoopFrequency = 0.0;
private double mMaximumLoopFrequency;
private double mDamping = Math.sqrt(2.0) / 2.0;
private double mAlphaGain;
private double mBetaGain;
private double mLoopPhase = 0.0;
// private double mLoopFrequency = 0.0;
private double mLoopFrequency = Math.PI * 2.0 * -10.0 / 48000.0;
private double mMaximumLoopFrequency;
private Complex mCurrentVector = new Complex(0, 0);
private Tracking mTracking = Tracking.SEARCHING;
private ITrackingStateListener mTrackingStateListener;
private boolean mAutomaticTrackingEnabled = true;
private Tracking mTracking = Tracking.NORMAL;
/**
* Costas Loop for tracking and correcting frequency error in a received carrier signal.
@@ -75,12 +64,12 @@ public class CostasLoop implements IPhaseLockedLoop
{
mLoopFrequency += correction;
if(mLoopFrequency > mMaximumLoopFrequency)
while(mLoopFrequency > mMaximumLoopFrequency)
{
mLoopFrequency -= 2.0 * mMaximumLoopFrequency;
}
if(mLoopFrequency < -mMaximumLoopFrequency)
while(mLoopFrequency < -mMaximumLoopFrequency)
{
mLoopFrequency += 2.0 * mMaximumLoopFrequency;
}
@@ -107,35 +96,6 @@ public class CostasLoop implements IPhaseLockedLoop
{
mTracking = tracking;
updateLoopBandwidth();
mLog.debug("Tracking: " + tracking.name());
if(mTrackingStateListener != null)
{
mTrackingStateListener.trackingStateChanged(tracking);
}
}
/**
* Sets the listener to receive notifications when the tracking state changes
*/
public void setTrackingStateListener(ITrackingStateListener listener)
{
mTrackingStateListener = listener;
}
/**
* Enables or disables automatic tracking state updates. When enabled, the loop will automatically increase or
* decrease the loop alpha/beta gain values based on the variance of the error tracking values submitted to the
* loop control. As the variance decreases, so will the gain values, and vice-versa. Setting this to disabled
* will force the tracker to retain the gain values associated with either the default or user-specified tracking
* value.
*
* @param enabled true (default) to enable automatic gain tracking
*/
public void setAutomaticTracking(boolean enabled)
{
mAutomaticTrackingEnabled = enabled;
}
/**
@@ -145,8 +105,16 @@ public class CostasLoop implements IPhaseLockedLoop
{
mLoopPhase += mLoopFrequency;
/* Keep the loop phase in bounds */
normalizePhase();
/* Normalize phase between +/- 2 * PI */
if(mLoopPhase > TWO_PI)
{
mLoopPhase -= TWO_PI;
}
if(mLoopPhase < -TWO_PI)
{
mLoopPhase += TWO_PI;
}
}
/**
@@ -171,11 +139,6 @@ public class CostasLoop implements IPhaseLockedLoop
return mLoopFrequency;
}
public double getMaximumLoopFrequency()
{
return mMaximumLoopFrequency;
}
/**
* Updates the costas loop frequency and phase to adjust for the phase
* error value
@@ -187,97 +150,18 @@ public class CostasLoop implements IPhaseLockedLoop
mLoopFrequency += (mBetaGain * phaseError);
mLoopPhase += mLoopFrequency + (mAlphaGain * phaseError);
/* Maintain phase between +/- 2 * PI */
normalizePhase();
/* Limit frequency to +/- maximum loop frequency */
limitFrequency();
// checkLoopBandwidth();
}
private void checkLoopBandwidth()
{
mErrorBuffer.put(mLoopFrequency);
double standardDeviation = mErrorBuffer.standardDeviation();
switch(mTracking)
{
case SEARCHING:
if(Tracking.COARSE.contains(standardDeviation))
{
setTracking(Tracking.COARSE);
}
break;
case COARSE:
if(Tracking.COARSE.contains(standardDeviation))
{
//Promote if possible - otherwise remain
if(Tracking.FINE.contains(standardDeviation))
{
setTracking(Tracking.FINE);
}
}
else
{
setTracking(Tracking.SEARCHING);
}
break;
case FINE:
if(Tracking.FINE.contains(standardDeviation))
{
//Promote if possible - otherwise remain
if(Tracking.LOCKED.contains(standardDeviation))
{
setTracking(Tracking.LOCKED);
}
}
else
{
setTracking(Tracking.COARSE);
}
break;
case LOCKED:
if(!Tracking.LOCKED.contains(standardDeviation))
{
setTracking(Tracking.FINE);
}
break;
}
}
public double getErrorMean()
{
return mErrorBuffer.mean();
}
public double getErrorVariance()
{
return mErrorBuffer.variance();
}
/**
* Normalizes the phase tracker to maintain within +/- 2 Pi
*/
private void normalizePhase()
{
while(mLoopPhase > TWO_PI)
/* Normalize phase between +/- 2 * PI */
if(mLoopPhase > TWO_PI)
{
mLoopPhase -= TWO_PI;
}
while(mLoopPhase < -TWO_PI)
if(mLoopPhase < -TWO_PI)
{
mLoopPhase += TWO_PI;
}
}
/**
* Constrains the frequency within the bounds of +/- loop frequency
*/
private void limitFrequency()
{
/* Limit frequency to +/- maximum loop frequency */
if(mLoopFrequency > mMaximumLoopFrequency)
{
mLoopFrequency = mMaximumLoopFrequency;
@@ -289,57 +173,10 @@ public class CostasLoop implements IPhaseLockedLoop
}
}
/**
* Tracking state listener interface for receiving updates when the tracking state of the costas loop changes
*/
public interface ITrackingStateListener
@Override
public void reset()
{
void trackingStateChanged(Tracking tracking);
mLoopPhase = 0.0;
mLoopFrequency = 0.0;
}
public static void main(String[] arguments)
{
DecimalFormat decimalFormat = new DecimalFormat("0.000000");
double sampleRate = 25000.0;
int errorFrequency = 411;
double loopBandwidth = 50.0;
Oscillator oscillator = new Oscillator(errorFrequency, (int)sampleRate);
CostasLoop costasLoop = new CostasLoop(sampleRate, 4800.0);
costasLoop.setTrackingStateListener(new ITrackingStateListener()
{
@Override
public void trackingStateChanged(Tracking tracking)
{
mLog.debug("Tracking State Changed: " + tracking.name());
}
});
for(int x = 0; x < 1000; x++)
{
Complex complex = oscillator.getComplex();
oscillator.rotate();
costasLoop.increment();
if(x % 5 == 0)
{
complex.multiply(costasLoop.getCurrentVector().conjugate());
double phaseError = complex.angle();
costasLoop.adjust(phaseError);
double loopFrequency = costasLoop.getLoopFrequency() * sampleRate / TWO_PI;
double maxFrequency = costasLoop.getMaximumLoopFrequency() * sampleRate / TWO_PI;
mLog.debug(x + " Frequency: " + errorFrequency +
" Loop:" + decimalFormat.format(loopFrequency) +
" Max:" + maxFrequency +
" Detected Error:" + decimalFormat.format(phaseError) +
" Avg:" + decimalFormat.format(costasLoop.getErrorMean()) +
" Var:" + decimalFormat.format(costasLoop.getErrorVariance()));
}
}
}
}

5
src/main/java/io/github/dsheirer/dsp/psk/pll/IPhaseLockedLoop.java
View File

@@ -52,5 +52,8 @@ public interface IPhaseLockedLoop
*/
Complex incrementAndGetCurrentVector();
/**
* Reset tracking to 0
*/
void reset();
}

45
src/main/java/io/github/dsheirer/dsp/psk/pll/Tracking.java
View File

@@ -15,26 +15,21 @@
******************************************************************************/
package io.github.dsheirer.dsp.psk.pll;
/**
* Phase Locked Loop (PLL) tracking bandwidth - controls how fast/slow the PLL tracks the carrier frequency
*/
public enum Tracking
{
// SEARCHING(50.0, 0.01, Math.PI),
// COARSE(100.0, 0.001, 0.01),
// FINE(150.0, 0.0001, 0.001),
// LOCKED(200.0, 0.0, 0.0001);
SEARCHING(100.0, 0.4, Math.PI),
COARSE(200.0, 0.2, 0.4),
FINE(400.0, 0.1, 0.2),
LOCKED(600.0, 0.0, 0.1);
FASTEST(50.0),
FAST(100.0),
NORMAL(200.0),
SLOW(400.0);
private double mLoopBandwidth;
private double mThresholdMinimum;
private double mThresholdMaximum;
Tracking(double loopBandwidth, double thresholdMinimum, double thresholdMaximum)
Tracking(double loopBandwidth)
{
mLoopBandwidth = loopBandwidth;
mThresholdMinimum = thresholdMinimum;
mThresholdMaximum = thresholdMaximum;
}
/**
@@ -44,28 +39,4 @@ public enum Tracking
{
return mLoopBandwidth;
}
/**
* Minimum error value for this entry
*/
public double getThresholdMinimum()
{
return mThresholdMinimum;
}
/**
* Maximum error value for this entry
*/
public double getThresholdMaximum()
{
return mThresholdMaximum;
}
/**
* Indicates if the error value is within the range for this entry
*/
public boolean contains(double standardDeviation)
{
return getThresholdMinimum() <= standardDeviation && standardDeviation < getThresholdMaximum();
}
}

6
src/main/java/io/github/dsheirer/instrument/gui/viewer/chart/EyeDiagramChart.java
View File

@@ -15,7 +15,7 @@
******************************************************************************/
package io.github.dsheirer.instrument.gui.viewer.chart;
import io.github.dsheirer.dsp.psk.SymbolDecisionData2;
import io.github.dsheirer.dsp.psk.SymbolDecisionData;
import io.github.dsheirer.sample.Listener;
import io.github.dsheirer.sample.complex.Complex;
import javafx.collections.FXCollections;
@@ -25,7 +25,7 @@ import javafx.scene.chart.NumberAxis;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class EyeDiagramChart extends LineChart implements Listener<SymbolDecisionData2>
public class EyeDiagramChart extends LineChart implements Listener<SymbolDecisionData>
{
private final static Logger mLog = LoggerFactory.getLogger(EyeDiagramChart.class);
@@ -81,7 +81,7 @@ public class EyeDiagramChart extends LineChart implements Listener<SymbolDecisio
}
@Override
public void receive(SymbolDecisionData2 symbolDecisionData)
public void receive(SymbolDecisionData symbolDecisionData)
{
Complex[] demodulated = symbolDecisionData.getDemodulated();

22
src/main/java/io/github/dsheirer/instrument/gui/viewer/decoder/P25Phase1Pane.java
View File

@@ -21,7 +21,7 @@ import io.github.dsheirer.instrument.gui.viewer.chart.EyeDiagramChart;
import io.github.dsheirer.instrument.gui.viewer.chart.PhaseLineChart;
import io.github.dsheirer.instrument.gui.viewer.chart.SymbolChart;
import io.github.dsheirer.module.decode.DecoderType;
import io.github.dsheirer.module.decode.p25.P25_C4FMDecoder2;
import io.github.dsheirer.module.decode.p25.P25_C4FMDecoder2Instrumented;
import io.github.dsheirer.sample.Broadcaster;
import io.github.dsheirer.sample.complex.ComplexBuffer;
import javafx.scene.layout.HBox;
@@ -42,7 +42,7 @@ public class P25Phase1Pane extends DecoderPane
private DoubleLineChart mPLLFrequencyLineChart;
private DoubleLineChart mSamplesPerSymbolLineChart;
private Broadcaster<ComplexBuffer> mFilteredBufferBroadcaster = new Broadcaster<>();
private P25_C4FMDecoder2 mDecoder = new P25_C4FMDecoder2(null);
private P25_C4FMDecoder2Instrumented mDecoder = new P25_C4FMDecoder2Instrumented(null);
public P25Phase1Pane()
{
@@ -52,15 +52,14 @@ public class P25Phase1Pane extends DecoderPane
private void init()
{
// addListener(getSampleLineChart());
addListener(getDecoder());
getDecoder().setDEBUGFilteredBufferListener(mFilteredBufferBroadcaster);
getDecoder().setDEBUGSymbolListener(getSymbolChart());
getDecoder().setDEBUGPLLPhaseErrorListener(getPLLPhaseErrorLineChart());
getDecoder().setDEBUGPLLFrequencyListener(getPLLFrequencyLineChart());
getDecoder().setDEBUGSymbolDecisionDataListener(getEyeDiagramChart());
getDecoder().setDEBUGSamplesPerSymbolListener(getSamplesPerSymbolLineChart());
getDecoder().setFilteredBufferListener(mFilteredBufferBroadcaster);
getDecoder().setSymbolListener(getSymbolChart());
getDecoder().setPLLPhaseErrorListener(getPLLPhaseErrorLineChart());
getDecoder().setPLLFrequencyListener(getPLLFrequencyLineChart());
getDecoder().setSymbolDecisionDataListener(getEyeDiagramChart());
getDecoder().setSamplesPerSymbolListener(getSamplesPerSymbolLineChart());
mFilteredBufferBroadcaster.addListener(getSampleLineChart());
HBox.setHgrow(getSampleChartBox(), Priority.ALWAYS);
@@ -77,10 +76,9 @@ public class P25Phase1Pane extends DecoderPane
double samplesPerSymbol = sampleRate / 4800.0;
getSampleLineChart().setSamplesPerSymbol((int)samplesPerSymbol);
// mSamplesPerSymbolLineChart = new DoubleLineChart( "Samples/Symbol", samplesPerSymbol - 1, samplesPerSymbol + 1, 0.1, 40);
}
private P25_C4FMDecoder2 getDecoder()
private P25_C4FMDecoder2Instrumented getDecoder()
{
return mDecoder;
}
@@ -167,7 +165,7 @@ public class P25Phase1Pane extends DecoderPane
{
if(mPLLFrequencyLineChart == null)
{
mPLLFrequencyLineChart = new DoubleLineChart( "PLL Frequency", -200, 200, 20, 40);
mPLLFrequencyLineChart = new DoubleLineChart( "PLL Frequency", -500, 500, 50, 40);
}
return mPLLFrequencyLineChart;

143
src/main/java/io/github/dsheirer/module/decode/p25/P25_C4FMDecoder2.java
View File

@@ -20,20 +20,16 @@ import io.github.dsheirer.dsp.filter.FilterFactory;
import io.github.dsheirer.dsp.filter.design.FilterDesignException;
import io.github.dsheirer.dsp.filter.fir.FIRFilterSpecification;
import io.github.dsheirer.dsp.filter.fir.complex.ComplexFIRFilter;
import io.github.dsheirer.dsp.gain.ComplexFeedForwardGainControl;
import io.github.dsheirer.dsp.psk.DQPSKDemodulator;
import io.github.dsheirer.dsp.psk.DQPSKSymbolPhaseErrorCalculator;
import io.github.dsheirer.dsp.psk.IQPSKSymbolDecoder;
import io.github.dsheirer.dsp.psk.ISymbolPhaseErrorCalculator;
import io.github.dsheirer.dsp.psk.InterpolatingSampleBuffer;
import io.github.dsheirer.dsp.psk.InterpolatingSampleBufferInstrumented;
import io.github.dsheirer.dsp.psk.QPSKStarSlicer;
import io.github.dsheirer.dsp.psk.QPSKSymbolDecoder;
import io.github.dsheirer.dsp.psk.SymbolDecisionData2;
import io.github.dsheirer.dsp.psk.pll.CostasLoop;
import io.github.dsheirer.dsp.psk.pll.Tracking;
import io.github.dsheirer.sample.Listener;
import io.github.dsheirer.sample.complex.Complex;
import io.github.dsheirer.sample.complex.ComplexBuffer;
import io.github.dsheirer.sample.complex.ComplexBufferToStreamConverter;
import io.github.dsheirer.sample.complex.IComplexBufferListener;
import io.github.dsheirer.source.tuner.frequency.FrequencyChangeEvent;
import org.slf4j.Logger;
@@ -46,36 +42,21 @@ import java.util.concurrent.ScheduledExecutorService;
public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListener, Listener<ComplexBuffer>
{
private final static Logger mLog = LoggerFactory.getLogger(P25_C4FMDecoder2.class);
private static final double SYMBOL_RATE = 4800;
private double mSampleRate;
protected static final double SYMBOL_RATE = 4800;
protected ISymbolPhaseErrorCalculator mSymbolPhaseErrorCalculator = new DQPSKSymbolPhaseErrorCalculator();
protected IQPSKSymbolDecoder mSymbolDecoder = new QPSKStarSlicer();
protected InterpolatingSampleBuffer mInterpolatingSampleBuffer;
protected DQPSKDemodulator mQPSKDemodulator;
protected CostasLoop mCostasLoop;
protected double mSampleRate;
private Map<Double,float[]> mBasebandFilters = new HashMap<>();
private ComplexFIRFilter mBasebandFilter;
private Map<Double,float[]> mSymbolFilters = new HashMap<>();
private ComplexFIRFilter mSymbolFilter;
private DQPSKDemodulator mQPSKDemodulator;
private CostasLoop mCostasLoop;
private ComplexBufferToStreamConverter mStreamConverter = new ComplexBufferToStreamConverter();
private ComplexFeedForwardGainControl mAGC = new ComplexFeedForwardGainControl(32);
private QPSKSymbolDecoder mQPSKSlicer = new QPSKSymbolDecoder();
private P25MessageFramer mMessageFramer;
private ISymbolPhaseErrorCalculator mSymbolPhaseErrorCalculator = new DQPSKSymbolPhaseErrorCalculator();
private IQPSKSymbolDecoder mSymbolDecoder = new QPSKStarSlicer();
private Listener<Complex> mDEBUGSymbolListener;
private Listener<Double> mDEBUGPLLPhaseErrorListener;
private Listener<Double> mDEBUGPLLFrequencyListener;
private Listener<SymbolDecisionData2> mDEBUGSymbolDecisionDataListener;
private Listener<Double> mDEBUGSamplesPerSymbolListener;
private Listener<ComplexBuffer> mFilteredSymbolListener;
public P25_C4FMDecoder2(AliasList aliasList)
{
super(aliasList);
setSampleRate(48600.0);
mStreamConverter.setListener(mAGC);
setSampleRate(48000.0);
}
public void setSampleRate(double sampleRate)
@@ -87,19 +68,12 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
mSampleRate = sampleRate;
mBasebandFilter = new ComplexFIRFilter(getBasebandFilter(), 1.0f);
mSymbolFilter = new ComplexFIRFilter(getSymbolFilter(), 1.0f);
mCostasLoop = new CostasLoop(mSampleRate, SYMBOL_RATE);
mCostasLoop.setTracking(Tracking.FINE);
mCostasLoop.setAutomaticTracking(false);
mInterpolatingSampleBuffer = new InterpolatingSampleBufferInstrumented((float)(sampleRate / SYMBOL_RATE));
mQPSKDemodulator = new DQPSKDemodulator(mCostasLoop, mSymbolPhaseErrorCalculator, mSymbolDecoder,
mSampleRate, SYMBOL_RATE);
mQPSKDemodulator.setSymbolListener(mDEBUGSymbolListener);
mQPSKDemodulator.setPLLErrorListener(mDEBUGPLLPhaseErrorListener);
mQPSKDemodulator.setPLLFrequencyListener(mDEBUGPLLFrequencyListener);
mQPSKDemodulator.setSymbolDecisionDataListener(mDEBUGSymbolDecisionDataListener);
mQPSKDemodulator.setSamplesPerSymbolListener(mDEBUGSamplesPerSymbolListener);
mInterpolatingSampleBuffer);
//Message framer can trigger a symbol-inversion correction to the PLL when detected
mMessageFramer = new P25MessageFramer(getAliasList(), mCostasLoop);
@@ -107,54 +81,16 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
mQPSKDemodulator.setDibitListener(mMessageFramer);
}
public void setDEBUGSymbolListener(Listener<Complex> listener)
{
mDEBUGSymbolListener = listener;
mQPSKDemodulator.setSymbolListener(listener);
}
public void setDEBUGPLLPhaseErrorListener(Listener<Double> listener)
{
mDEBUGPLLPhaseErrorListener = listener;
mQPSKDemodulator.setPLLErrorListener(listener);
}
public void setDEBUGPLLFrequencyListener(Listener<Double> listener)
{
mDEBUGPLLFrequencyListener = listener;
mQPSKDemodulator.setPLLFrequencyListener(listener);
}
public void setDEBUGFilteredBufferListener(Listener<ComplexBuffer> listener)
{
mFilteredSymbolListener = listener;
}
public void setDEBUGSymbolDecisionDataListener(Listener<SymbolDecisionData2> listener)
{
mDEBUGSymbolDecisionDataListener = listener;
mQPSKDemodulator.setSymbolDecisionDataListener(listener);
}
public void setDEBUGSamplesPerSymbolListener(Listener<Double> listener)
{
mDEBUGSamplesPerSymbolListener = listener;
mQPSKDemodulator.setSamplesPerSymbolListener(listener);
}
@Override
public void receive(ComplexBuffer complexBuffer)
{
ComplexBuffer basebandFiltered = mBasebandFilter.filter(complexBuffer);
// ComplexBuffer symbolFiltered = mSymbolFilter.filter(complexBuffer);
// ComplexBuffer symbolFiltered = complexBuffer;
ComplexBuffer symbolFiltered = basebandFiltered;
mQPSKDemodulator.receive(symbolFiltered);
ComplexBuffer filtered = filter(complexBuffer);
mQPSKDemodulator.receive(filtered);
}
if(mFilteredSymbolListener != null)
{
mFilteredSymbolListener.receive(symbolFiltered);
}
protected ComplexBuffer filter(ComplexBuffer complexBuffer)
{
return mBasebandFilter.filter(complexBuffer);
}
private double getSampleRate()
@@ -170,11 +106,11 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
{
FIRFilterSpecification specification = FIRFilterSpecification.lowPassBuilder()
.sampleRate((int)getSampleRate())
.passBandCutoff(6000)
.passBandCutoff(5100)
.passBandAmplitude(1.0)
.passBandRipple(0.01)
.stopBandAmplitude(0.0)
.stopBandStart(6250)
.stopBandStart(6500)
.stopBandRipple(0.01)
.build();
@@ -200,20 +136,6 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
return filter;
}
private float[] getSymbolFilter()
{
float[] filter = mSymbolFilters.get(getSampleRate());
if(filter == null)
{
float samplesPerSymbol = (float)(getSampleRate() / 4800.0);
filter = FilterFactory.getRootRaisedCosine(samplesPerSymbol, 40, 0.2f);
mSymbolFilters.put(getSampleRate(), filter);
}
return filter;
}
public void dispose()
{
super.dispose();
@@ -221,15 +143,6 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
mBasebandFilter.dispose();
mBasebandFilter = null;
mStreamConverter.dispose();
mStreamConverter = null;
mAGC.dispose();
mAGC = null;
mQPSKSlicer.dispose();
mQPSKSlicer = null;
mMessageFramer.dispose();
mMessageFramer = null;
}
@@ -252,7 +165,15 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
@Override
public void receive(FrequencyChangeEvent frequencyChangeEvent)
{
//Ignored
switch(frequencyChangeEvent.getEvent())
{
case NOTIFICATION_FREQUENCY_CHANGE:
case NOTIFICATION_FREQUENCY_CORRECTION_CHANGE:
case NOTIFICATION_CHANNEL_FREQUENCY_CORRECTION_CHANGE:
case NOTIFICATION_SAMPLE_RATE_CHANGE:
mCostasLoop.reset();
break;
}
}
};
}
@@ -271,20 +192,16 @@ public class P25_C4FMDecoder2 extends P25Decoder implements IComplexBufferListen
@Override
public void reset()
{
// TODO Auto-generated method stub
mCostasLoop.reset();
}
@Override
public void start(ScheduledExecutorService executor)
{
// TODO Auto-generated method stub
}
@Override
public void stop()
{
// TODO Auto-generated method stub
}
}

109
src/main/java/io/github/dsheirer/module/decode/p25/P25_C4FMDecoder2Instrumented.java Normal file
View File

@@ -0,0 +1,109 @@
/*******************************************************************************
* sdr-trunk
* Copyright (C) 2014-2018 Dennis Sheirer
*
* 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, either 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 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/>
*
******************************************************************************/
package io.github.dsheirer.module.decode.p25;
import io.github.dsheirer.alias.AliasList;
import io.github.dsheirer.dsp.psk.DQPSKDemodulatorInstrumented;
import io.github.dsheirer.dsp.psk.InterpolatingSampleBufferInstrumented;
import io.github.dsheirer.dsp.psk.SymbolDecisionData;
import io.github.dsheirer.sample.Listener;
import io.github.dsheirer.sample.complex.Complex;
import io.github.dsheirer.sample.complex.ComplexBuffer;
public class P25_C4FMDecoder2Instrumented extends P25_C4FMDecoder2
{
private Listener<Double> mPLLPhaseErrorListener;
private Listener<Double> mPLLFrequencyListener;
private Listener<Double> mSamplesPerSymbolListener;
private Listener<Complex> mSymbolListener;
private Listener<ComplexBuffer> mFilteredSymbolListener;
private Listener<SymbolDecisionData> mSymbolDecisionDataListener;
public P25_C4FMDecoder2Instrumented(AliasList aliasList)
{
super(aliasList);
}
/**
* Overrides the filter method so that we can capture the filtered samples for instrumentation
*/
protected ComplexBuffer filter(ComplexBuffer complexBuffer)
{
ComplexBuffer filtered = super.filter(complexBuffer);
if(mFilteredSymbolListener != null)
{
mFilteredSymbolListener.receive(filtered);
}
return filtered;
}
/**
* Overrides this method so we can correctly configure for instrumented operations
*/
public void setSampleRate(double sampleRate)
{
super.setSampleRate(sampleRate);
InterpolatingSampleBufferInstrumented instrumentedBuffer = new InterpolatingSampleBufferInstrumented((float)(sampleRate / SYMBOL_RATE));
mInterpolatingSampleBuffer = instrumentedBuffer;
DQPSKDemodulatorInstrumented instrumented = new DQPSKDemodulatorInstrumented(mCostasLoop,
mSymbolPhaseErrorCalculator, mSymbolDecoder, instrumentedBuffer, mSampleRate);
mQPSKDemodulator = instrumented;
instrumented.setSymbolListener(mSymbolListener);
instrumented.setPLLErrorListener(mPLLPhaseErrorListener);
instrumented.setPLLFrequencyListener(mPLLFrequencyListener);
instrumented.setSymbolDecisionDataListener(mSymbolDecisionDataListener);
instrumented.setSamplesPerSymbolListener(mSamplesPerSymbolListener);
}
public void setSymbolListener(Listener<Complex> listener)
{
mSymbolListener = listener;
((DQPSKDemodulatorInstrumented)mQPSKDemodulator).setSymbolListener(listener);
}
public void setPLLPhaseErrorListener(Listener<Double> listener)
{
mPLLPhaseErrorListener = listener;
((DQPSKDemodulatorInstrumented)mQPSKDemodulator).setPLLErrorListener(listener);
}
public void setPLLFrequencyListener(Listener<Double> listener)
{
mPLLFrequencyListener = listener;
((DQPSKDemodulatorInstrumented)mQPSKDemodulator).setPLLFrequencyListener(listener);
}
public void setFilteredBufferListener(Listener<ComplexBuffer> listener)
{
mFilteredSymbolListener = listener;
}
public void setSymbolDecisionDataListener(Listener<SymbolDecisionData> listener)
{
mSymbolDecisionDataListener = listener;
((DQPSKDemodulatorInstrumented)mQPSKDemodulator).setSymbolDecisionDataListener(listener);
}
public void setSamplesPerSymbolListener(Listener<Double> listener)
{
mSamplesPerSymbolListener = listener;
((DQPSKDemodulatorInstrumented)mQPSKDemodulator).setSamplesPerSymbolListener(listener);
}
}

2
src/main/java/io/github/dsheirer/module/decode/p25/message/tsbk/osp/control/SyncBroadcast.java
View File

@@ -78,7 +78,7 @@ public class SyncBroadcast extends TSBKMessage
if( isMicroslotsLockedToMinuteRollover() )
{
sb.append( " MICROSLOT-MINUTE ROLLOVER:LOCKED" );
sb.append( " MICROSLOT-MINUTE ROLLOVER:SLOW" );
}
else
{