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[WIP] Updating dsp modules to accept variable sample rate I/Q streams

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and creating a new audio resampler.
This commit is contained in:
Denny
2018-02-09 05:29:07 -05:00
parent 96d9d6f750
commit 28cb9d9407
15 changed files with 369 additions and 171 deletions
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9
src/main/java/io/github/dsheirer/source/tuner/channel/TunerChannelSource.java
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@@ -180,15 +180,18 @@ public abstract class TunerChannelSource extends ComplexSource implements ISourc
case NOTIFICATION_SAMPLE_RATE_CHANGE:
setSampleRate(sourceEvent.getValue().doubleValue());
break;
case NOTIFICATION_FREQUENCY_AND_SAMPLE_RATE_LOCKED:
case NOTIFICATION_FREQUENCY_AND_SAMPLE_RATE_UNLOCKED:
case NOTIFICATION_FREQUENCY_CORRECTION_CHANGE:
//no-op
break;
//Request events from the consumer
case REQUEST_CHANNEL_FREQUENCY_CORRECTION_CHANGE:
setFrequencyCorrection(sourceEvent.getValue().longValue());
break;
default:
mLog.error("Ignoring unrecognized source event: " + sourceEvent.getEvent() + " from [" +
sourceEvent.getSource().getClass() + "]");
(sourceEvent.hasSource() ? sourceEvent.getSource().getClass() : "") + "]");
break;
}
}

30
src/main/java/io/github/dsheirer/source/tuner/manager/TunerChannelSourceManager.java
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@@ -181,18 +181,39 @@ public class TunerChannelSourceManager extends ChannelSourceManager
long bestIntegralFrequency = getIntegralFrequency(channels);
//See if we can reuse the current frequency
//Strategy 1: reuse the current frequency if it's a good integral and the channels fit
if(isIntegralSpacing(currentCenterFrequency, bestIntegralFrequency) &&
isValidCenterFrequency(channels, currentCenterFrequency))
{
return currentCenterFrequency;
}
//Start by placing the first channel at the minimum location within the tuner bandwidth
double usableHalfBandwidth = mTunerController.getUsableHalfBandwidth();
//Strategy 2: start by placing the center frequency exactly one channel width below the first channel frequency
//and iteratively increase it one channel width at a time. This optimally places the channels nearest to the
//center of the bandwidth
long start = channels.first().getFrequency() - (int)mPolyphaseChannelManager.getChannelBandwidth();
if(isValidCenterFrequency(channels, start))
{
return start;
}
while(start - channels.first().getMinFrequency() < usableHalfBandwidth)
{
start += (int)mPolyphaseChannelManager.getChannelBandwidth();
if(isValidCenterFrequency(channels, start))
{
return start;
}
}
//Strategy 3: start by placing the first channel at the minimum location within the tuner bandwidth
double startFrequency = channels.first().getMinFrequency() + usableHalfBandwidth;
//Align the test frequency to the next greater integral frequency placing to place the first channel at the
//Align the test frequency to the next greater integral frequency placing the first channel at the
// minimum extreme of the available bandwidth as a starting location
double delta = Math.abs(startFrequency - bestIntegralFrequency);
double adjustment = delta % mPolyphaseChannelManager.getChannelBandwidth();
@@ -221,7 +242,8 @@ public class TunerChannelSourceManager extends ChannelSourceManager
currentChannel++;
}
//If we can't find an integral center frequency, choose a frequency that will fit the channels
//Strategy 4: brute force walk across the spectrum 1 hertz at a time looking for a center frequency that will
//fit all channels
long testFrequency = channels.first().getMinFrequency() + mTunerController.getUsableHalfBandwidth();
long minimumFrequency = testFrequency - availableTestBandwidth;

4
src/main/java/io/github/dsheirer/source/tuner/test/TestTunerController.java
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@@ -33,8 +33,8 @@ public class TestTunerController extends TunerController
public static final long MINIMUM_FREQUENCY = 1l;
public static final long MAXIMUM_FREQUENCY = 1000000000l;
public static final int SAMPLE_RATE = 100000;
public static final int DC_NOISE_BANDWIDTH = 5000;
public static final double USABLE_BANDWIDTH_PERCENTAGE = .90;
public static final int DC_NOISE_BANDWIDTH = 0;
public static final double USABLE_BANDWIDTH_PERCENTAGE = 1.00;
public static final int SPECTRAL_FRAME_RATE = 20;
public static final long SAMPLE_GENERATION_INTERVAL = 1000 / SPECTRAL_FRAME_RATE;