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

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new symbol timing error detector.
This commit is contained in:
Denny
2018-02-25 05:04:20 -05:00
parent 3d1ac30646
commit a0630102e6
17 changed files with 811 additions and 98 deletions
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105
src/main/java/io/github/dsheirer/dsp/psk/QPSKStarSlicer.java
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@@ -1,3 +1,18 @@
/*******************************************************************************
* 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.symbol.Dibit;
@@ -5,54 +20,54 @@ import io.github.dsheirer.sample.Broadcaster;
import io.github.dsheirer.sample.Listener;
import io.github.dsheirer.sample.complex.Complex;
public class QPSKStarSlicer implements Listener<Complex>
public class QPSKStarSlicer implements IQPSKSymbolDecoder, Listener<Complex>
{
private Broadcaster<Dibit> mBroadcaster = new Broadcaster<Dibit>();
private Broadcaster<Dibit> mBroadcaster = new Broadcaster<Dibit>();
/**
* Slices a ComplexSample representing a phase shifted symbol according to
* the following constellation pattern:
*
* 00 | 01
* ---|---
* 10 | 11
*/
public QPSKStarSlicer()
{
}
public void dispose()
{
mBroadcaster.dispose();
mBroadcaster = null;
}
/**
* Slices a Complex sample representing a phase shifted symbol according to the following constellation pattern:
*
* 00 +3 | 01 +1
* ------|------
* 10 -1 | 11 -1
*/
public QPSKStarSlicer()
{
}
public void addListener( Listener<Dibit> listener )
{
mBroadcaster.addListener( listener );
}
public void dispose()
{
mBroadcaster.dispose();
mBroadcaster = null;
}
public void removeListener( Listener<Dibit> listener )
{
mBroadcaster.removeListener( listener );
}
public void addListener(Listener<Dibit> listener)
{
mBroadcaster.addListener(listener);
}
public void removeListener(Listener<Dibit> listener)
{
mBroadcaster.removeListener(listener);
}
@Override
public void receive(Complex sample)
{
mBroadcaster.broadcast(decode(sample));
}
@Override
public Dibit decode(Complex sample)
{
if(sample.inphase() > 0)
{
return sample.quadrature() > 0 ? Dibit.D00_PLUS_1 : Dibit.D10_MINUS_1;
}
else
{
return sample.quadrature() > 0 ? Dibit.D01_PLUS_3 : Dibit.D11_MINUS_3;
}
}
@Override
public void receive( Complex sample )
{
mBroadcaster.broadcast( decide( sample ) );
}
public static Dibit decide( Complex sample )
{
if( sample.inphase() > 0 )
{
return sample.quadrature() > 0 ? Dibit.D00_PLUS_1 : Dibit.D10_MINUS_1;
}
else
{
return sample.quadrature() > 0 ? Dibit.D01_PLUS_3 : Dibit.D11_MINUS_3;
}
}
}