Working unoptimzied WFM just mono (AF baseband)

include-gpl/dsp/fftfilt.h

@@ -5,7 +5,7 @@
 #ifndef	_FFTFILT_H
 #define	_FFTFILT_H
 
-#include "complex.h"
+#include <complex>
 #include "gfft.h"
 
 //----------------------------------------------------------------------
@@ -13,6 +13,20 @@
 class fftfilt {
 enum {NONE, BLACKMAN, HAMMING, HANNING};
 
+public:
+	typedef std::complex<float> cmplx;
+
+	fftfilt(float f1, float f2, int len);
+	fftfilt(float f, int len);
+	~fftfilt();
+// f1 < f2 ==> bandpass
+// f1 > f2 ==> band reject
+	void create_filter(float f1, float f2);
+	void rtty_filter(float);
+
+	int runFilt(const cmplx& in, cmplx **out);
+	int runSSB(const cmplx& in, cmplx **out, bool usb);
+
 protected:
 	int flen;
 	int flen2;
@@ -36,18 +50,6 @@ protected:
 				 0.08 * cos(4.0 * M_PI * i / len));
 	}
 	void init_filter();
-
-public:
-	fftfilt(float f1, float f2, int len);
-	fftfilt(float f, int len);
-	~fftfilt();
-// f1 < f2 ==> bandpass
-// f1 > f2 ==> band reject
-	void create_filter(float f1, float f2);
-	void rtty_filter(float);
-
-	int runFilt(const cmplx& in, cmplx **out);
-	int runSSB(const cmplx& in, cmplx **out, bool usb);
 };
 
 
@@ -55,6 +57,12 @@ public:
 /* Sliding FFT filter from Fldigi */
 class sfft {
 #define K1 0.99999
+public:
+	typedef std::complex<float> cmplx;
+	sfft(int len);
+	~sfft();
+	void run(const cmplx& input);
+	void fetch(float *result);
 private:
 	int fftlen;
 	int first;
@@ -64,11 +72,6 @@ private:
 	vrot_bins_pair *vrot_bins;
 	cmplx *delay;
 	float k2;
-public:
-	sfft(int len);
-	~sfft();
-	void run(const cmplx& input);
-	void fetch(float *result);
 };
 
 #endif

plugins/channel/CMakeLists.txt

@@ -5,5 +5,6 @@ add_subdirectory(am)
 add_subdirectory(nfm)
 add_subdirectory(ssb)
 add_subdirectory(tcpsrc)
+add_subdirectory(wfm)
 
 #add_subdirectory(tetra)

plugins/channel/ssb/ssbdemod.cpp

@@ -62,7 +62,7 @@ void SSBDemod::configure(MessageQueue* messageQueue, Real Bandwidth, Real LowCut
 void SSBDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iterator end, bool positiveOnly)
 {
 	Complex ci;
-	cmplx *sideband;
+	fftfilt::cmplx *sideband;
 	int n_out;
 
 	for(SampleVector::const_iterator it = begin; it < end; ++it) {

plugins/channel/tcpsrc/tcpsrc.cpp

@@ -70,7 +70,7 @@ void TCPSrc::setSpectrum(MessageQueue* messageQueue, bool enabled)
 void TCPSrc::feed(SampleVector::const_iterator begin, SampleVector::const_iterator end, bool positiveOnly)
 {
 	Complex ci;
-	cmplx* sideband;
+	fftfilt::cmplx* sideband;
 	Real l, r;
 
 	m_sampleBuffer.clear();

plugins/channel/wfm/wfmdemod.cpp

@@ -23,7 +23,7 @@
 #include "dsp/pidcontroller.h"
 #include "wfmdemod.h"
 
-#include <iostream>
+//#include <iostream>
 
 MESSAGE_CLASS_DEFINITION(WFMDemod::MsgConfigureWFMDemod, Message)
 
@@ -31,13 +31,14 @@ WFMDemod::WFMDemod(AudioFifo* audioFifo, SampleSink* sampleSink) :
 	m_sampleSink(sampleSink),
 	m_audioFifo(audioFifo)
 {
-	m_config.m_inputSampleRate = 96000;
+	m_config.m_inputSampleRate = 384000;
 	m_config.m_inputFrequencyOffset = 0;
 	m_config.m_rfBandwidth = 180000;
 	m_config.m_afBandwidth = 15000;
 	m_config.m_squelch = -60.0;
 	m_config.m_volume = 2.0;
 	m_config.m_audioSampleRate = 48000;
+	m_rfFilter = new fftfilt(-50000.0 / 384000.0, 50000.0 / 384000.0, rfFilterFftLength);
 
 	apply();
 
@@ -49,6 +50,8 @@ WFMDemod::WFMDemod(AudioFifo* audioFifo, SampleSink* sampleSink) :
 
 WFMDemod::~WFMDemod()
 {
+	if (m_rfFilter)
+		delete m_rfFilter;
 }
 
 void WFMDemod::configure(MessageQueue* messageQueue, Real rfBandwidth, Real afBandwidth, Real volume, Real squelch)
@@ -92,16 +95,51 @@ Real angleDist(Real a, Real b)
 void WFMDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iterator end, bool firstOfBurst)
 {
 	Complex ci;
+	fftfilt::cmplx *rf;
+	int rf_out;
 
 	if (m_audioFifo->size() <= 0)
 		return;
 
-	for(SampleVector::const_iterator it = begin; it != end; ++it) {
+	for (SampleVector::const_iterator it = begin; it != end; ++it)
+	{
 		Complex c(it->real() / 32768.0, it->imag() / 32768.0);
 		c *= m_nco.nextIQ();
 
+		rf_out = m_rfFilter->runFilt(c, &rf); // filter RF before demod
+
+		for (int i =0 ; i  <rf_out; i++)
 		{
-			if(m_interpolator.interpolate(&m_interpolatorDistanceRemain, c, &ci))
+			Real x = rf[i].real() * m_lastSample.real() + rf[i].imag() * m_lastSample.imag();
+			Real y = rf[i].real() * m_lastSample.imag() - rf[i].imag() * m_lastSample.real();
+			Real demod = atan2(x,y) / M_PI;
+			m_lastSample = rf[i];
+
+			Complex e(demod, 0);
+
+			if(m_interpolator.interpolate(&m_interpolatorDistanceRemain, e, &ci))
+			{
+				quint16 sample = (qint16)(ci.real() * 3000 * m_running.m_volume);
+				m_sampleBuffer.push_back(Sample(sample, sample));
+				m_audioBuffer[m_audioBufferFill].l = sample;
+				m_audioBuffer[m_audioBufferFill].r = sample;
+				++m_audioBufferFill;
+
+				if(m_audioBufferFill >= m_audioBuffer.size())
+				{
+					uint res = m_audioFifo->write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 1);
+					if(res != m_audioBufferFill)
+						qDebug("lost %u samples", m_audioBufferFill - res);
+					m_audioBufferFill = 0;
+				}
+
+				m_interpolatorDistanceRemain += m_interpolatorDistance;
+			}
+		}
+
+#if 0
+		{
+			if(m_interpolator.interpolate(&m_interpolatorDistanceRemain, e, &ci))
 			{
 				m_sampleBuffer.push_back(Sample(ci.real() * 32767.0, ci.imag() * 32767.0));
 
@@ -113,10 +151,12 @@ void WFMDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iter
 				if(m_squelchState > 0) {
 					m_squelchState--;
 
+					/*
 					Real argument = arg(ci);
 					argument /= M_PI;
 					Real demod = argument - m_lastArgument;
 					m_lastArgument = argument;
+					*/
 
 
 					//ci *= 32768.0;
@@ -178,7 +218,10 @@ void WFMDemod::feed(SampleVector::const_iterator begin, SampleVector::const_iter
 				m_interpolatorDistanceRemain += m_interpolatorDistance;
 			}
 		}
+#endif
+
 	}
+
 	if(m_audioBufferFill > 0) {
 		uint res = m_audioFifo->write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 1);
 		if(res != m_audioBufferFill)
@@ -234,20 +277,31 @@ void WFMDemod::apply()
 {
 
 	if((m_config.m_inputFrequencyOffset != m_running.m_inputFrequencyOffset) ||
-		(m_config.m_inputSampleRate != m_running.m_inputSampleRate)) {
+		(m_config.m_inputSampleRate != m_running.m_inputSampleRate))
+	{
 		m_nco.setFreq(-m_config.m_inputFrequencyOffset, m_config.m_inputSampleRate);
 	}
 
 	if((m_config.m_inputSampleRate != m_running.m_inputSampleRate) ||
-		(m_config.m_rfBandwidth != m_running.m_rfBandwidth)) {
+		(m_config.m_afBandwidth != m_running.m_afBandwidth))
-		std::cerr << "WFMDemod::apply: in=" << m_config.m_inputSampleRate << ", rf=" << m_config.m_rfBandwidth << std::endl;
+	{
-		m_interpolator.create(16, m_config.m_inputSampleRate, m_config.m_rfBandwidth / 2.2);
+		m_interpolator.create(16, m_config.m_inputSampleRate, m_config.m_afBandwidth);
-		m_interpolatorDistanceRemain = 0;
+		m_interpolatorDistanceRemain = (Real) m_config.m_inputSampleRate / m_config.m_audioSampleRate;
 		m_interpolatorDistance =  m_config.m_inputSampleRate / m_config.m_audioSampleRate;
 	}
 
+	if((m_config.m_inputSampleRate != m_running.m_inputSampleRate) ||
+		(m_config.m_rfBandwidth != m_running.m_rfBandwidth) ||
+		(m_config.m_inputFrequencyOffset != m_running.m_inputFrequencyOffset))
+	{
+		Real lowCut = (m_config.m_inputFrequencyOffset - (m_config.m_rfBandwidth / 2.0)) / m_config.m_inputSampleRate;
+		Real hiCut  = (m_config.m_inputFrequencyOffset + (m_config.m_rfBandwidth / 2.0)) / m_config.m_inputSampleRate;
+		m_rfFilter->create_filter(lowCut, hiCut);
+	}
+
 	if((m_config.m_afBandwidth != m_running.m_afBandwidth) ||
-		(m_config.m_audioSampleRate != m_running.m_audioSampleRate)) {
+		(m_config.m_audioSampleRate != m_running.m_audioSampleRate))
+	{
 		m_lowpass.create(21, m_config.m_audioSampleRate, m_config.m_afBandwidth);
 	}
 
@@ -262,4 +316,13 @@ void WFMDemod::apply()
 	m_running.m_squelch = m_config.m_squelch;
 	m_running.m_volume = m_config.m_volume;
 	m_running.m_audioSampleRate = m_config.m_audioSampleRate;
+
+	/*
+	std::cerr << "WFMDemod::apply: in=" << m_config.m_inputSampleRate
+			<< ", df=" << m_config.m_inputFrequencyOffset
+			<< ", rfbw=" << m_config.m_rfBandwidth
+			<< ", afbw=" << m_config.m_afBandwidth
+			<< std::endl;
+	*/
+
 }

plugins/channel/wfm/wfmdemod.h

@@ -24,9 +24,12 @@
 #include "dsp/interpolator.h"
 #include "dsp/lowpass.h"
 #include "dsp/movingaverage.h"
+#include "dsp/fftfilt.h"
 #include "audio/audiofifo.h"
 #include "util/message.h"
 
+#define rfFilterFftLength 1024
+
 class AudioFifo;
 
 class WFMDemod : public SampleSink {
@@ -111,6 +114,7 @@ private:
 	Real m_interpolatorDistance;
 	Real m_interpolatorDistanceRemain;
 	Lowpass<Real> m_lowpass;
+	fftfilt* m_rfFilter;
 
 	Real m_squelchLevel;
 	int m_squelchState;

plugins/channel/wfm/wfmdemodgui.cpp

@@ -17,6 +17,16 @@ const int WFMDemodGUI::m_rfBW[] = {
 	48000, 80000, 120000, 140000, 160000, 180000, 200000, 220000, 250000
 };
 
+int requiredBW(int rfBW)
+{
+	if (rfBW <= 48000)
+		return 48000;
+	else if (rfBW < 100000)
+		return 96000;
+	else
+		return 384000;
+}
+
 WFMDemodGUI* WFMDemodGUI::create(PluginAPI* pluginAPI)
 {
 	WFMDemodGUI* gui = new WFMDemodGUI(pluginAPI);
@@ -208,7 +218,7 @@ void WFMDemodGUI::applySettings()
 {
 	setTitleColor(m_channelMarker->getColor());
 	m_channelizer->configure(m_threadedSampleSink->getMessageQueue(),
-		256000, // TODO: this is where requested sample rate is specified
+		requiredBW(m_rfBW[ui->rfBW->value()]), // TODO: this is where requested sample rate is specified
 		m_channelMarker->getCenterFrequency());
 	ui->deltaFrequency->setValue(abs(m_channelMarker->getCenterFrequency()));
 	ui->deltaMinus->setChecked(m_channelMarker->getCenterFrequency() < 0);

sdrbase/dsp/channelizer.cpp

@@ -96,11 +96,17 @@ bool Channelizer::handleMessage(Message* cmd)
 void Channelizer::applyConfiguration()
 {
 	freeFilterChain();
-	//std::cerr << "Channelizer::applyConfiguration in=" << m_inputSampleRate << ", req=" << m_requestedOutputSampleRate << std::endl;
 	m_currentCenterFrequency = createFilterChain(
 		m_inputSampleRate / -2, m_inputSampleRate / 2,
 		m_requestedCenterFrequency - m_requestedOutputSampleRate / 2, m_requestedCenterFrequency + m_requestedOutputSampleRate / 2);
 	m_currentOutputSampleRate = m_inputSampleRate / (1 << m_filterStages.size());
+	/*
+	std::cerr << "Channelizer::applyConfiguration in=" << m_inputSampleRate
+			<< ", req=" << m_requestedOutputSampleRate
+			<< ", out=" << m_currentOutputSampleRate
+			<< ", fc=" << m_currentCenterFrequency
+			<< std::endl;
+	*/
 }
 
 Channelizer::FilterStage::FilterStage(Mode mode) :