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P25 - adds direct frequency control for the C4FM symbol filter to adjust the tuner channel for frequency correction.

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dennis.sheirer
2015-01-19 16:20:37 +00:00
parent cc5edd4790
commit 1c0da75c01
7 changed files with 146 additions and 41 deletions
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57
src/dsp/fsk/C4FMSymbolFilter.java
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@@ -13,8 +13,13 @@ import org.slf4j.LoggerFactory;
import sample.real.RealSampleListener;
import sample.real.RealSampleProvider;
import source.tuner.FrequencyChangeBroadcaster;
import source.tuner.FrequencyChangeEvent;
import source.tuner.FrequencyChangeEvent.Attribute;
import source.tuner.FrequencyChangeListener;
public class C4FMSymbolFilter implements RealSampleListener,
public class C4FMSymbolFilter implements FrequencyChangeBroadcaster,
RealSampleListener,
RealSampleProvider,
Instrumentable
{
@@ -180,7 +185,8 @@ public class C4FMSymbolFilter implements RealSampleListener,
private static final double K_FINE_FREQUENCY = 0.125;
/* Frequency correction broadcast threshold */
private static final double COARSE_FREQUENCY_DEADBAND = 1.66;
// private static final double COARSE_FREQUENCY_DEADBAND = 1.66;
private static final double COARSE_FREQUENCY_DEADBAND = 1.20;
/* 2.0 symbol spread gives -3, -1, 1, 3 */
private float mSymbolSpread = 2.0f;
@@ -194,6 +200,9 @@ public class C4FMSymbolFilter implements RealSampleListener,
private int mHistoryLast = 0;
private RealSampleListener mListener;
private FrequencyChangeListener mFrequencyChangeListener;
private long mFrequencyCorrection;
private float mGain = 15.4f;
@@ -219,6 +228,11 @@ public class C4FMSymbolFilter implements RealSampleListener,
{
}
public long getFrequencyCorrection()
{
return mFrequencyCorrection;
}
@Override
public void receive( float sample )
{
@@ -311,13 +325,24 @@ public class C4FMSymbolFilter implements RealSampleListener,
mFineFrequencyCorrection += ( symbolError * K_FINE_FREQUENCY );
// /* send frequency correction */
// if( Math.abs( mCoarseFrequencyCorrection ) > COARSE_FREQUENCY_DEADBAND )
// {
// mLog.debug( "Frequency Correction [" +
// ( mCoarseFrequencyCorrection > 0 ? "-" : "+" ) +
// mCoarseFrequencyCorrection + "]" );
// }
/* send frequency correction */
if( Math.abs( mCoarseFrequencyCorrection ) > COARSE_FREQUENCY_DEADBAND )
{
if( mFrequencyChangeListener != null )
{
mFrequencyCorrection += (
500 * ( mCoarseFrequencyCorrection > 0 ? 1 : -1 ) );
mFrequencyChangeListener.frequencyChanged(
new FrequencyChangeEvent( Attribute.FREQUENCY_ERROR,
mFrequencyCorrection ) );
/* reset internal frequency error tracker */
mCoarseFrequencyCorrection = 0;
mLog.debug( "Frequency Corrected: " + mFrequencyCorrection );
}
}
if( mSymbolSpreadTap != null )
{
@@ -343,7 +368,7 @@ public class C4FMSymbolFilter implements RealSampleListener,
{
mListener = null;
}
@Override
public List<Tap> getTaps()
{
@@ -379,4 +404,16 @@ public class C4FMSymbolFilter implements RealSampleListener,
mSymbolSpreadTap = null;
}
}
@Override
public void addListener( FrequencyChangeListener listener )
{
mFrequencyChangeListener = listener;
}
@Override
public void removeListener( FrequencyChangeListener listener )
{
mFrequencyChangeListener = null;
}
}