GitHub/sdrtrunk
1
0
Fork 0
mirror of https://github.com/DSheirer/sdrtrunk.git synced 2026-11-12 08:37:25 -05:00
Code Issues Packages Projects Releases 2 Wiki Activity

Resolves issue with AFC and frequency change event handling,

Browse Source 
specifically for P25 C4FM frequency tracking.

-Clarifies frequency change event naming and adds request/notitification
events for channel frequency correction type events

-Removes DC offset filter from P25 C4FM demodulator which was operating
independently of the AFC tracking component within the C4FM symbol
filter.

-Changed FCD tuner center DC spike buffer size after detecting that the
DC center spike was influencing the P25 C4FM filter frequency tracker
whenever the tuner's center frequency was changed to bring the channel
boundary within 3 kHz of the center spike -- set it to 5 kHz to provide
a better buffer.

-Updated spectral channel display to provide better indication of
automatic frequency control (yellow line) versus channel frequency
This commit is contained in:
denny
2015-12-31 09:08:26 -05:00
parent 81aff1cdef
commit 9c305b0732
24 changed files with 191 additions and 166 deletions
Download Patch File Download Diff File Expand all files Collapse all files

81
src/source/tuner/TunerChannelSource.java
View File

@@ -35,7 +35,7 @@ import sample.complex.ComplexBuffer;
import source.ComplexSource;
import source.SourceException;
import source.tuner.frequency.FrequencyChangeEvent;
import source.tuner.frequency.FrequencyChangeEvent.Attribute;
import source.tuner.frequency.FrequencyChangeEvent.Event;
import source.tuner.frequency.FrequencyChangeListener;
import controller.ThreadPoolManager;
import controller.ThreadPoolManager.ThreadType;
@@ -66,8 +66,8 @@ public class TunerChannelSource extends ComplexSource
private ScheduledFuture<?> mTaskHandle;
private long mTunerFrequency = 0;
private int mTunerFrequencyError = 0;
private int mTunerSampleRate;
private int mChannelFrequencyCorrection = 0;
private DecimationProcessor mDecimationProcessor = new DecimationProcessor();
@@ -92,11 +92,11 @@ public class TunerChannelSource extends ComplexSource
mMixer = new Oscillator( frequencyOffset, mTuner.getSampleRate() );
/* Fire a sample rate change event to get the decimation chain setup */
/* Fire a sample rate change event to setup the decimation chain */
frequencyChanged( new FrequencyChangeEvent(
Attribute.SAMPLE_RATE, mTuner.getSampleRate() ) );
Event.SAMPLE_RATE_CHANGE_NOTIFICATION, mTuner.getSampleRate() ) );
/* Schedule the decimation task to run 50 times a second */
/* Schedule the decimation task to run every 20 ms (50 iterations/second) */
mTaskHandle = mThreadPoolManager.scheduleFixedRate( ThreadType.DECIMATION,
mDecimationProcessor, 20, TimeUnit.MILLISECONDS );
@@ -183,26 +183,44 @@ public class TunerChannelSource extends ComplexSource
{
mDecimationFilter.removeListener();
}
/**
* Handler for frequency change events received from the tuner and channel
* frequency correction events received from the channel consumer/listener
*/
@Override
public void frequencyChanged( FrequencyChangeEvent event )
{
/* Send change to Automatic Frequency Control if it exists */
// Echo the event to the registered event listener
if( mFrequencyChangeListener != null )
{
mFrequencyChangeListener.frequencyChanged( event );
}
switch( event.getAttribute() )
switch( event.getEvent() )
{
case SAMPLE_RATE_ERROR:
case FREQUENCY_CHANGE_NOTIFICATION:
mTunerFrequency = event.getValue().longValue();
updateMixerFrequencyOffset();
break;
case SAMPLE_RATE:
case CHANNEL_FREQUENCY_CORRECTION_CHANGE_REQUEST:
mChannelFrequencyCorrection = event.getValue().intValue();
updateMixerFrequencyOffset();
if( mFrequencyChangeListener != null )
{
mFrequencyChangeListener.frequencyChanged(
new FrequencyChangeEvent(
Event.CHANNEL_FREQUENCY_CORRECTION_CHANGE_NOTIFICATION,
mChannelFrequencyCorrection ) );
}
break;
case SAMPLE_RATE_CHANGE_NOTIFICATION:
int sampleRate = event.getValue().intValue();
if( mTunerSampleRate != sampleRate )
{
/* Set the oscillator to the new frequency */
mMixer.setSampleRate( sampleRate );
/* Get new decimation filter */
@@ -220,33 +238,30 @@ public class TunerChannelSource extends ComplexSource
mTunerSampleRate = sampleRate;
}
break;
case FREQUENCY_ERROR:
mTunerFrequencyError = event.getValue().intValue();
long frequencyErrorOffset = mTunerFrequency -
mTunerChannel.getFrequency() -
mTunerFrequencyError;
mMixer.setFrequency( frequencyErrorOffset );
break;
case FREQUENCY:
long frequency = event.getValue().longValue();
/* If the frequency is updated, the AFC will also get reset, so
* we don't include the frequency error value here */
mTunerFrequencyError = 0;
long frequencyOffset = frequency - mTunerChannel.getFrequency();
mMixer.setFrequency( frequencyOffset );
mTunerFrequency = frequency;
break;
default:
break;
}
}
/**
* Calculates the local mixer frequency offset from the tuned frequency,
* channel's requested frequency, and channel frequency correction.
*/
private void updateMixerFrequencyOffset()
{
long offset = mTunerFrequency -
mTunerChannel.getFrequency() -
mChannelFrequencyCorrection;
mMixer.setFrequency( offset );
mLog.debug( "VCO Updated -"
+ " Tuner:" + mTunerFrequency
+ " Channel:" + mTunerChannel.getFrequency()
+ " Correction:" + mChannelFrequencyCorrection
+ " Mixer: " + offset );
}
public int getSampleRate() throws SourceException
{
return CHANNEL_RATE;