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#39 WIP polyphase channelizers.

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Denny
2017-11-18 05:50:00 -05:00
parent 5281679b7f
commit b3e4bd6a9c
16 changed files with 217 additions and 90 deletions
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57
src/source/tuner/test/SampleGenerator.java
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@@ -19,6 +19,8 @@
package source.tuner.test;
import dsp.mixer.LowPhaseNoiseOscillator;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import sample.Listener;
import sample.complex.ComplexBuffer;
import util.ThreadPool;
@@ -28,12 +30,40 @@ import java.util.concurrent.TimeUnit;
public class SampleGenerator
{
private final static Logger mLog = LoggerFactory.getLogger(SampleGenerator.class);
private LowPhaseNoiseOscillator mOscillator;
private int mSweepUpdateInterval;
private Listener<ComplexBuffer> mListener;
private long mInterval;
private int mSamplesPerInterval;
private ScheduledFuture<?> mScheduledFuture;
/**
* Generates complex sample buffers at the specified sample rate with a unity gain tone at the specified
* frequency. This generator runs via a scheduled thread pool and generates samples at the specified time
* interval.
*
* @param sampleRate of the complex samples
* @param frequency of the tone produced by the generator
* @param interval in milliseconds for generating samples
* @param sweepUpdateRate to turn on sweeping of the tone frequency where the frequency is incremented by the
* rate specified at each interval, resetting to 1 Hz after reaching/exceeding the highest frequency.
*/
public SampleGenerator(int sampleRate, long frequency, long interval, int sweepUpdateRate)
{
if(Math.abs(sweepUpdateRate) >= sampleRate)
{
throw new IllegalArgumentException("Sweep update rate cannot be greater than sample rate");
}
mOscillator = new LowPhaseNoiseOscillator(sampleRate, frequency);
mInterval = interval;
mSweepUpdateInterval = sweepUpdateRate;
updateSamplesPerInterval();
}
/**
* Generates complex sample buffers at the specified sample rate with a unity gain tone at the specified
* frequency. This generator runs via a scheduled thread pool and generates samples at the specified time
@@ -45,10 +75,7 @@ public class SampleGenerator
*/
public SampleGenerator(int sampleRate, long frequency, long interval)
{
mOscillator = new LowPhaseNoiseOscillator(sampleRate, frequency);
mInterval = interval;
updateSamplesPerInterval();
this(sampleRate, frequency, interval, 0);
}
/**
@@ -56,7 +83,9 @@ public class SampleGenerator
*/
private void updateSamplesPerInterval()
{
mSamplesPerInterval = (int)((double)mOscillator.getSampleRate() * ((double)mInterval / 1000.0) * 2.0);
mSamplesPerInterval = (int)((double)mOscillator.getSampleRate() * ((double)mInterval / 1000.0));
mLog.debug("Sample Generator: " + mSamplesPerInterval + " samples every " + mInterval + " ms.");
}
/**
@@ -141,6 +170,24 @@ public class SampleGenerator
{
float[] samples = mOscillator.generate(mSamplesPerInterval);
mListener.receive(new ComplexBuffer(samples));
if(mSweepUpdateInterval != 0)
{
long updatedFrequency = mOscillator.getFrequency() + mSweepUpdateInterval;
if(updatedFrequency > mOscillator.getSampleRate() / 2)
{
mOscillator.setFrequency(mOscillator.getSampleRate() / -2);
}
else if(updatedFrequency < mOscillator.getSampleRate() / -2)
{
mOscillator.setFrequency(mOscillator.getSampleRate() / 2);
}
else
{
mOscillator.setFrequency(updatedFrequency);
}
}
}
}
}