P25 - enhancement for LSM demod phase lock errors - adds new sync pattern detectors to detect Costas Loop phase lock errors and apply immediate correction to enable accurate symbol slicing.

src/bits/ISyncDetectListener.java

@@ -0,0 +1,6 @@
+package bits;
+
+public interface ISyncDetectListener
+{
+	public void syncDetected();
+}

src/bits/ISyncProcessor.java

@@ -0,0 +1,6 @@
+package bits;
+
+public interface ISyncProcessor
+{
+	public void checkSync( long value );
+}

src/bits/MultiSyncPatternMatcher.java

@@ -0,0 +1,104 @@
+/*******************************************************************************
+ *     SDR Trunk 
+ *     Copyright (C) 2014 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 bits;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Multi-Sync pattern matcher.  Accepts multiple sync detector objects for 
+ * comparision against the incoming bit stream.
+ * 
+ * Note: works for sync patterns up to 63 bits (integer size - 1 ) long.  
+ * If a 64 bit or larger sync pattern is applied, then the wrapping feature
+ * of the Long.rotate methods will wrap the MSB around to the LSB and
+ * corrupt the matching value.
+ *
+ */
+public class MultiSyncPatternMatcher
+{
+	private List<ISyncProcessor> mSyncProcessors = new ArrayList<ISyncProcessor>();
+	
+	private long mBits = 0;
+	private long mMask = 0;
+	
+	public MultiSyncPatternMatcher( int syncSize )
+	{
+		assert( syncSize < 64 );
+		
+		//Setup a bit mask of all ones the length of the sync pattern
+		mMask = (long)( ( Math.pow( 2, syncSize ) ) - 1 );
+	}
+	
+	/**
+	 * Processes two bits before checking sync processors for a match.
+	 */
+	public void receive( boolean bit1, boolean bit2 )
+	{
+		mBits = Long.rotateLeft( mBits, 1 );
+		
+		mBits &= mMask;
+		
+		if( bit1 )
+		{
+			mBits += 1;
+		}
+
+		mBits = Long.rotateLeft( mBits, 1 );
+		
+		mBits &= mMask;
+		
+		if( bit2 )
+		{
+			mBits += 1;
+		}
+
+		for( ISyncProcessor processor: mSyncProcessors )
+		{
+			processor.checkSync( mBits );
+		}
+	}
+	
+	/**
+	 * Processes one bit before checking sync processors for a match.
+	 */
+	public void receive( boolean bit )
+	{
+		mBits = Long.rotateLeft( mBits, 1 );
+		
+		mBits &= mMask;
+		
+		if( bit )
+		{
+			mBits += 1;
+		}
+
+		for( ISyncProcessor processor: mSyncProcessors )
+		{
+			processor.checkSync( mBits );
+		}
+	}
+
+	/**
+	 * Adds a sync processor to receive the bit stream.
+	 */
+	public void add( ISyncProcessor processor )
+	{
+		mSyncProcessors.add( processor );
+	}
+}

src/bits/SoftSyncDetector.java

@@ -0,0 +1,38 @@
+package bits;
+
+public class SoftSyncDetector implements ISyncProcessor
+{
+	private ISyncDetectListener mListener;
+	private long mPattern;
+	private int mThreshold;
+	
+	public SoftSyncDetector( ISyncDetectListener listener, long pattern, int threshold )
+	{
+		this( pattern, threshold );
+		
+		mListener = listener;
+	}
+	
+	public SoftSyncDetector( long pattern, int threshold )
+	{
+		mPattern = pattern;
+		mThreshold = threshold;
+	}
+
+	@Override
+	public void checkSync( long value )
+	{
+		long difference = value ^ mPattern;
+		
+		if( ( difference == 0 || Long.bitCount( difference ) <= mThreshold ) &&
+			  mListener != null )
+		{
+			mListener.syncDetected();
+		}
+	}
+	
+	public void setListener( ISyncDetectListener listener )
+	{
+		mListener = listener;
+	}
+}

src/bits/SyncDetector.java

@@ -0,0 +1,33 @@
+package bits;
+
+public class SyncDetector implements ISyncProcessor
+{
+	private long mPattern;
+	private ISyncDetectListener mListener;
+
+	public SyncDetector( long pattern )
+	{
+		mPattern = pattern;
+	}
+	
+	public SyncDetector( long pattern, ISyncDetectListener listener )
+	{
+		this( pattern );
+		
+		mListener = listener;
+	}
+	
+	public void setListener( ISyncDetectListener listener )
+	{
+		mListener = listener;
+	}
+
+	@Override
+	public void checkSync( long value )
+	{
+		if( value == mPattern && mListener != null )
+		{
+			mListener.syncDetected();
+		}
+	}
+}

src/decode/p25/P25Decoder.java

@@ -88,8 +88,8 @@ public class P25Decoder extends Decoder
 	private C4FMSlicer mC4FMSlicer;
 	private QPSKStarSlicer mCQPSKSlicer;
 	
-	/* Message framers and handlers */
-	private P25MessageFramer mNormalFramer;
+	/* Message framers and processors */
+	private P25MessageFramer mMessageFramer;
 	private P25MessageProcessor mMessageProcessor;
 	
 	/* Audio */
@@ -111,9 +111,19 @@ public class P25Decoder extends Decoder
 		mMessageProcessor = new P25MessageProcessor( mAliasList );
 		mMessageProcessor.addMessageListener( this );
 
-        mNormalFramer = new P25MessageFramer( 
-                FrameSync.P25_PHASE1.getSync(), 64, false, mAliasList );
-        mNormalFramer.setListener( mMessageProcessor );
+		if( modulation == Modulation.CQPSK )
+		{
+			/* Provide message framer with reference to the demod so that it 
+			 * can detect and issue corrections for costas phase lock errors */
+			mCQPSKDemodulator = new CQPSKDemodulator();
+	        mMessageFramer = new P25MessageFramer( mAliasList, mCQPSKDemodulator );
+		}
+		else
+		{
+	        mMessageFramer = new P25MessageFramer( mAliasList );
+		}
+		
+        mMessageFramer.setListener( mMessageProcessor );
 
         /* Setup demodulation chains based on sample type (real or complex) and 
          * modulation (C4FM or CQPSK) */
@@ -136,13 +146,12 @@ public class P25Decoder extends Decoder
 						.getRootRaisedCosine( 10, 34, 0.2 ), 1.0 );
 				mAGC.setListener( mRootRaisedCosineFilter );
 
-				mCQPSKDemodulator = new CQPSKDemodulator();
 				mRootRaisedCosineFilter.setListener( mCQPSKDemodulator );
 				
 				mCQPSKSlicer = new QPSKStarSlicer();
 				mCQPSKDemodulator.setListener( mCQPSKSlicer );
 				
-				mCQPSKSlicer.addListener( mNormalFramer );
+				mCQPSKSlicer.addListener( mMessageFramer );
 			}
 			else /* C4FM */
 			{
@@ -172,7 +181,7 @@ public class P25Decoder extends Decoder
 			mC4FMSlicer = new C4FMSlicer();
 			mSymbolFilter.setListener( mC4FMSlicer );
 			
-	        mC4FMSlicer.addListener( mNormalFramer );
+	        mC4FMSlicer.addListener( mMessageFramer );
 		}
 		
 		mAudioOutput = new P25AudioOutput( resourceManager );

src/decode/p25/P25MessageFramer.java

@@ -11,7 +11,10 @@ import sample.Listener;
 import alias.AliasList;
 import bits.BinaryMessage;
 import bits.BitSetFullException;
-import bits.SyncPatternMatcher;
+import bits.ISyncDetectListener;
+import bits.MultiSyncPatternMatcher;
+import bits.SoftSyncDetector;
+import bits.SyncDetector;
 import decode.p25.message.P25Message;
 import decode.p25.message.hdu.HDUMessage;
 import decode.p25.message.ldu.LDU1Message;
@@ -27,20 +30,32 @@ import decode.p25.message.tdu.lc.TDULinkControlMessage;
 import decode.p25.message.tsbk.TSBKMessage;
 import decode.p25.message.tsbk.TSBKMessageFactory;
 import decode.p25.reference.DataUnitID;
+import dsp.psk.CQPSKDemodulator;
 import dsp.symbol.Dibit;
+import dsp.symbol.FrameSync;
 import edac.BCH_63_16_11;
 import edac.CRC;
 import edac.CRCP25;
 
 public class P25MessageFramer implements Listener<Dibit>
 {
-	private static final int SYNC_PATTERN_MISMATCH_THRESHOLD = 2;
-	
 	private final static Logger mLog = 
-							LoggerFactory.getLogger( P25MessageFramer.class );
+			LoggerFactory.getLogger( P25MessageFramer.class );
+
+	/* Determines the threshold for sync pattern soft matching */
+	private static final int SYNC_PATTERN_SOFT_MATCH_THRESHOLD = 4;
+
+	/* Costas Loop phase lock error correction values.  A phase lock error of
+	 * 90 degrees requires a correction of 1/4 of the symbol rate (1200Hz).  An 
+	 * error of 180 degrees requires a correction of 1/2 of the symbol rate
+	 * (2400Hz) */
+	public static final double SYMBOL_FREQUENCY = 2.0d * Math.PI * 4800.0d / 48000.0d;
+	public static final double PHASE_CORRECTION_90_DEGREES = SYMBOL_FREQUENCY / 4.0d; 
+	public static final double PHASE_CORRECTION_180_DEGREES = SYMBOL_FREQUENCY / 2.0d; 
 	
+	private MultiSyncPatternMatcher mMatcher = new MultiSyncPatternMatcher( 48 ); 
 	private ArrayList<P25MessageAssembler> mAssemblers =
-			new ArrayList<P25MessageAssembler>();
+						new ArrayList<P25MessageAssembler>();
 
 	public static final int TSBK_BEGIN = 64;
 	public static final int TSBK_CRC_START = 144;
@@ -60,31 +75,41 @@ public class P25MessageFramer implements Listener<Dibit>
 	
 	private Listener<Message> mListener;
 	private AliasList mAliasList;
-	private SyncPatternMatcher mMatcher;
-	private boolean mInverted = false;
+
 	private Trellis_1_2_Rate mHalfRate = new Trellis_1_2_Rate();
 	private Trellis_3_4_Rate mThreeQuarterRate = new Trellis_3_4_Rate();
 	private BCH_63_16_11 mNIDDecoder = new BCH_63_16_11();
 	
 	/**
-	 * Constructs a C4FM message framer to receive a stream of C4FM symbols and
+	 * Constructs a P25 message framer to receive a stream of symbols and
 	 * detect the sync pattern then capture the following stream of symbols up
 	 * to the message length, and then broadcast that bit buffer to the registered
 	 * listener.
-	 * 
-	 * @param sync - sync pattern (maximum of 63 bits)
-	 * @param messageLength - in bits
-	 * @param inverted - optional flag to indicate the symbol stream should be
-	 * uninverted prior to processing 
 	 */
-	public P25MessageFramer( long sync, 
-	                         int messageLength, 
-	                         boolean inverted,
-	                         AliasList aliasList )
+	public P25MessageFramer( AliasList aliasList )
 	{
-		mMatcher = new SyncPatternMatcher( sync, SYNC_PATTERN_MISMATCH_THRESHOLD );
-		mInverted = inverted;
 		mAliasList = aliasList;
+		
+		SoftSyncDetector primarySyncDetector = new SoftSyncDetector( 
+			FrameSync.P25_PHASE1_NORMAL.getSync(), SYNC_PATTERN_SOFT_MATCH_THRESHOLD );
+		
+		primarySyncDetector.setListener( new ISyncDetectListener()
+		{
+			@Override
+			public void syncDetected()
+			{
+	        	for( P25MessageAssembler assembler: mAssemblers )
+	        	{
+	        		if( !assembler.isActive() )
+	        		{
+	        			assembler.setActive( true );
+	        			break;
+	        		}
+	        	}
+			}
+		} );
+		
+		mMatcher.add( primarySyncDetector );
 
 		/**
 		 * We use two message assemblers to catch any sync detections, so that
@@ -98,6 +123,22 @@ public class P25MessageFramer implements Listener<Dibit>
 		mAssemblers.add( new P25MessageAssembler() );
 	}
 	
+	public P25MessageFramer( AliasList aliasList, CQPSKDemodulator demodulator )
+	{
+		this( aliasList );
+
+		/* For CQPSK, we include 3 additional sync detectors to watch for and
+		 * correction +/-90 and 180 degree costas loop phase lock errors */
+		mMatcher.add( new CostasPhaseErrorDetector( FrameSync.P25_PHASE1_ERROR_90_CCW, 
+				demodulator, PHASE_CORRECTION_90_DEGREES  ) );
+
+		mMatcher.add( new CostasPhaseErrorDetector( FrameSync.P25_PHASE1_ERROR_90_CW, 
+				demodulator, -PHASE_CORRECTION_90_DEGREES  ) );
+
+		mMatcher.add( new CostasPhaseErrorDetector( FrameSync.P25_PHASE1_ERROR_180, 
+				demodulator, PHASE_CORRECTION_180_DEGREES  ) );
+	}
+	
 	private void dispatch( Message message )
 	{
 		if( mListener != null )
@@ -109,9 +150,6 @@ public class P25MessageFramer implements Listener<Dibit>
 	@Override
     public void receive( Dibit symbol )
     {
-    	mMatcher.receive( symbol.getBit1() );
-    	mMatcher.receive( symbol.getBit2() );
-
     	for( P25MessageAssembler assembler: mAssemblers )
     	{
     		if( assembler.isActive() )
@@ -125,27 +163,7 @@ public class P25MessageFramer implements Listener<Dibit>
     		}
     	}
     	
-        /* Check for sync match and activate a message assembler, if we can
-         * find an inactive assembler.  Otherwise, ignore and log the issue */
-    	if( mMatcher.matches() )
-    	{
-    		boolean found = false;
-    		
-        	for( P25MessageAssembler assembler: mAssemblers )
-        	{
-        		if( !assembler.isActive() )
-        		{
-        			assembler.setActive( true );
-        			found = true;
-        			break;
-        		}
-        	}
-        	
-        	if( !found )
-        	{
-            	mLog.debug( "no inactive P25 message assemblers available" );
-        	}
-    	}
+		mMatcher.receive( symbol.getBit1(), symbol.getBit2() );
     }
 
     public void setListener( Listener<Message> listener )
@@ -258,12 +276,10 @@ public class P25MessageFramer implements Listener<Dibit>
 					break;
 				case HDU:
 					mComplete = true;
-					mMatcher.setSoftMode( true );
                     dispatch( new HDUMessage( mMessage.copy(), mDUID, mAliasList ) );
 					break;
 				case LDU1:
 					mComplete = true;
-					mMatcher.setSoftMode( true );
 					
 					LDU1Message ldu1 = new LDU1Message( mMessage.copy(), 
 							mDUID, mAliasList );
@@ -273,11 +289,9 @@ public class P25MessageFramer implements Listener<Dibit>
 					break;
 				case LDU2:
 					mComplete = true;
-					mMatcher.setSoftMode( true );
                     dispatch( new LDU2Message( mMessage.copy(), mDUID, mAliasList ) );
 					break;
 				case PDU0:
-					mMatcher.setSoftMode( false );
 
 					/* Remove interleaving */
 					P25Interleave.deinterleaveData( mMessage, PDU0_BEGIN, PDU0_END );
@@ -397,8 +411,6 @@ public class P25MessageFramer implements Listener<Dibit>
 					mComplete = true;
 					break;
 				case PDUC:
-					mMatcher.setSoftMode( true );
-
 					/* De-interleave the latest block*/
 					P25Interleave.deinterleaveData( mMessage, 
 							mMessage.size() - 196, mMessage.size() );
@@ -447,12 +459,10 @@ public class P25MessageFramer implements Listener<Dibit>
 					}
 					break;
 				case TDU:
-					mMatcher.setSoftMode( true );
                     dispatch( new TDUMessage( mMessage.copy(), mDUID, mAliasList ) );
 					mComplete = true;
 					break;
 				case TDULC:
-					mMatcher.setSoftMode( true );
 					TDULinkControlMessage tdulc =  new TDULinkControlMessage( 
 							mMessage.copy(), mDUID, mAliasList );
 
@@ -463,7 +473,6 @@ public class P25MessageFramer implements Listener<Dibit>
 					mComplete = true;
 					break;
 				case TSBK1:
-					mMatcher.setSoftMode( true );
 					/* Remove interleaving */
 					P25Interleave.deinterleaveData( mMessage, TSBK_BEGIN, TSBK_END );
 	
@@ -602,4 +611,50 @@ public class P25MessageFramer implements Listener<Dibit>
         	return mActive;
         }
     }
+    
+    /**
+     * Sync pattern detector to listen for costas loop phase lock errors and 
+     * apply a phase correction to the costas loop so that we don't miss any 
+     * messages.
+     * 
+     * When the costas loop locks with a +/- 90 degree or 180 degree phase 
+     * error, the slicer will incorrectly apply the symbol pattern rotated left
+     * or right by the phase error.  However, we can detect these rotated sync
+     * patterns and apply immediate phase correction so that message processing
+     * can continue. 
+     */
+    public class CostasPhaseErrorDetector extends SyncDetector
+    {
+    	private CQPSKDemodulator mDemodulator;
+    	private double mCorrection;
+    	
+    	public CostasPhaseErrorDetector( FrameSync frameSync, 
+    			CQPSKDemodulator demodulator, double correction )
+    	{
+    		super( frameSync.getSync() );
+
+    		mDemodulator = demodulator;
+    		
+    		mCorrection = correction;
+
+    		setListener( new ISyncDetectListener()
+			{
+				@Override
+				public void syncDetected()
+				{
+					mDemodulator.correctPhaseError( mCorrection );
+
+					/* Since we detected a sync pattern, start a message assembler */
+		        	for( P25MessageAssembler assembler: mAssemblers )
+		        	{
+		        		if( !assembler.isActive() )
+		        		{
+		        			assembler.setActive( true );
+		        			break;
+		        		}
+		        	}
+				}
+			} );
+    	}
+    }
 }

src/dsp/psk/CQPSKDemodulator.java

@@ -76,6 +76,8 @@ public class CQPSKDemodulator implements Instrumentable,
 	
 	private GardnerSymbolTiming mGardnerDetector = new GardnerSymbolTiming();
 	
+	private CostasLoop mCostasLoop = new CostasLoop();
+	
 	private FrequencyChangeListener mFrequencyChangeListener;
 	
 	private EyeDiagramDataTap mEyeDiagramDataTap;
@@ -90,6 +92,17 @@ public class CQPSKDemodulator implements Instrumentable,
 		mGardnerDetector.receive( sample );
 	}
 	
+	/**
+	 * Applies a phase correction value to the costas loop to correct when a
+	 * phase lock error is detected in the binary output stream.
+	 * 
+	 * @param correction - value in radians
+	 */
+	public void correctPhaseError( double correction )
+	{
+		mCostasLoop.correctPhaseError( correction );
+	}
+	
 	/**
 	 * Constrains value to the range of ( -maximum <> maximum )
 	 */
@@ -207,7 +220,7 @@ public class CQPSKDemodulator implements Instrumentable,
 
 		/* Sampling point */
 		private float mMu = 10.0f;
-		private float mGainMu = 0.25f;
+		private float mGainMu = 0.1f;
 		
 		/* Samples per symbol */
 		private float mOmega = 10.0f;
@@ -215,8 +228,6 @@ public class CQPSKDemodulator implements Instrumentable,
 		private float mOmegaRel = 0.005f;
 		private float mOmegaMid = 10.0f;
 
-		private CostasLoop mCostasLoop = new CostasLoop();
-		
 		private QPSKInterpolator mInterpolator = new QPSKInterpolator( 1.0f );
 		
 		private ComplexSample mPreviousSample = new ComplexSample( 0.0f, 0.0f );
@@ -347,7 +358,7 @@ public class CQPSKDemodulator implements Instrumentable,
 		public static final double TWO_PI = 2.0 * Math.PI;
 		
 		private static final float MAXIMUM_FREQUENCY = 
-				( 1200.0f * (float)TWO_PI ) / 48000.0f;
+				( 2400.0f * (float)TWO_PI ) / 48000.0f;
 		
 		/* http://www.trondeau.com/blog/2011/8/13/control-loop-gain-values.html */
 		private float mDamping = (float)Math.sqrt( 2.0 ) / 2.0f;
@@ -374,6 +385,33 @@ public class CQPSKDemodulator implements Instrumentable,
 		{
 		}
 		
+		/**
+		 * Applies a phase correction value to the current phasor.  Use this 
+		 * method to apply correction when a +/- 90, or 180 degree phase error
+		 * is detected in the binary output stream.
+		 * 
+		 * If the supplied correction value places the loop frequency outside
+		 * of the max frequency, then the frequency will be corrected 360
+		 * degrees in the opposite direction to maintain within the max
+		 * frequency bounds.
+		 * 
+		 * @param correction - correction value in radians
+		 */
+		public void correctPhaseError( double correction )
+		{
+			mLoopFrequency += correction;
+		
+			if( mLoopFrequency > MAXIMUM_FREQUENCY )
+			{
+				mLoopFrequency -= 2.0d * MAXIMUM_FREQUENCY;
+			}
+			
+			if( mLoopFrequency < -MAXIMUM_FREQUENCY )
+			{
+				mLoopFrequency += 2.0d * MAXIMUM_FREQUENCY;
+			}
+		}
+		
 		/**
 		 * Increments the phase of the loop
 		 */

src/dsp/psk/QPSKStarSlicer.java

@@ -13,9 +13,9 @@ public class QPSKStarSlicer implements Listener<ComplexSample>
 	 * Slices a ComplexSample representing a phase shifted symbol according to
 	 * the following constellation pattern:
 	 * 
-	 *    11 | 01
+	 *    00 | 01
 	 *    ---|---
-	 *    10 | 00
+	 *    10 | 11
 	 */
 	public QPSKStarSlicer()
 	{

src/dsp/symbol/FrameSync.java

@@ -2,8 +2,10 @@ package dsp.symbol;
 
 public enum FrameSync
 {
-	P25_PHASE1( 0x5575F5FF77FFl ),          //+3 +3 +3 +3 +3 -3 +3 +3 -3 -3 +3 +3 -3 -3 -3 -3 +3 -3 +3 -3 -3 -3 -3 -3
-	P25_PHASE1_INVERTED( 0xFFDF5F55DD55l );
+	P25_PHASE1_ERROR_90_CCW( 0xFFEFAFAAEEAAl ),
+	P25_PHASE1_NORMAL(       0x5575F5FF77FFl ),  // +33333 -3 +33 -33 +33 -3333 +3 -3 +3 -33333
+	P25_PHASE1_ERROR_90_CW(  0x001050551155l ),
+	P25_PHASE1_ERROR_180(    0xAA8A0A008800l );
 	
 	private long mSync;
 	

src/sample/complex/ComplexSample.java

@@ -293,6 +293,14 @@ public class ComplexSample implements Serializable
 		return (float)Math.atan2( y(), x() );
 	}
 
+	/**
+	 * Angle of this sample in degrees
+	 */
+	public float polarAngle()
+	{
+		return (float)Math.toDegrees( angle() );
+	}
+
 	/**
 	 * Provides an approximate magnitude value for this sample.
 	 */
@@ -313,13 +321,18 @@ public class ComplexSample implements Serializable
 	
 	public static void main( String[] args )
 	{
-		ComplexSample s1 = new ComplexSample( 0.24414134f, -0.6026385f );
-		ComplexSample s2 = new ComplexSample( -0.09531293f, -0.7052474f );
+		double SYMBOL_FREQUENCY = 2.0d * Math.PI * 4800.0d / 48000.0d;
+		double PHASE_CORRECTION_90_DEGREES = SYMBOL_FREQUENCY / 4.0d; 
+		double PHASE_CORRECTION_180_DEGREES = SYMBOL_FREQUENCY / 2.0d; 
+
+		double angle = Math.PI / 4;
+
+		ComplexSample s1 = new ComplexSample( (float)Math.sin( angle ), (float)Math.cos( angle ) );
+		ComplexSample s2 = new ComplexSample( (float)Math.sin( -angle ), (float)Math.cos( -angle ) );
 		
 		ComplexSample symbol = ComplexSample.multiply( s1, s2.conjugate() );
 
-		mLog.debug( "S1 Mag:" + s1.magnitude() + " S2 Mag:" + s2.magnitude() + " SymMag:" + symbol.magnitude() );
-		mLog.debug( "S1:" + s1 + " S2:" + s2 + " Symbol:" + symbol );
+		mLog.debug( "S1:" + s1.polarAngle() + " S2:" + s2.polarAngle() + " Symbol:" + symbol.polarAngle() );
 		
 	}
 }