AM Demodulator: removed useless AF lowpass filtering and its associated GUI items

plugins/channelrx/demodam/amdemod.cpp

@@ -36,8 +36,7 @@ AMDemod::AMDemod() :
 
 	m_config.m_inputSampleRate = 96000;
 	m_config.m_inputFrequencyOffset = 0;
-	m_config.m_rfBandwidth = 12500;
+	m_config.m_rfBandwidth = 5000;
-	m_config.m_afBandwidth = 3000;
 	m_config.m_squelch = -40.0;
 	m_config.m_volume = 2.0;
 	m_config.m_audioSampleRate = DSPEngine::instance()->getAudioSampleRate();
@@ -59,9 +58,9 @@ AMDemod::~AMDemod()
 	DSPEngine::instance()->removeAudioSink(&m_audioFifo);
 }
 
-void AMDemod::configure(MessageQueue* messageQueue, Real rfBandwidth, Real afBandwidth, Real volume, Real squelch, bool audioMute)
+void AMDemod::configure(MessageQueue* messageQueue, Real rfBandwidth, Real volume, Real squelch, bool audioMute)
 {
-	Message* cmd = MsgConfigureAMDemod::create(rfBandwidth, afBandwidth, volume, squelch, audioMute);
+	Message* cmd = MsgConfigureAMDemod::create(rfBandwidth, volume, squelch, audioMute);
 	messageQueue->push(cmd);
 }
 
@@ -150,7 +149,6 @@ bool AMDemod::handleMessage(const Message& cmd)
 		MsgConfigureAMDemod& cfg = (MsgConfigureAMDemod&) cmd;
 
 		m_config.m_rfBandwidth = cfg.getRFBandwidth();
-		m_config.m_afBandwidth = cfg.getAFBandwidth();
 		m_config.m_volume = cfg.getVolume();
 		m_config.m_squelch = cfg.getSquelch();
 		m_config.m_audioMute = cfg.getAudioMute();
@@ -159,7 +157,6 @@ bool AMDemod::handleMessage(const Message& cmd)
 
 		qDebug() << "AMDemod::handleMessage: MsgConfigureAMDemod:"
 				<< " m_rfBandwidth: " << m_config.m_rfBandwidth
-				<< " m_afBandwidth: " << m_config.m_afBandwidth
 				<< " m_volume: " << m_config.m_volume
 				<< " m_squelch: " << m_config.m_squelch
 				<< " m_audioMute: " << m_config.m_audioMute;
@@ -182,7 +179,8 @@ void AMDemod::apply()
 	}
 
 	if((m_config.m_inputSampleRate != m_running.m_inputSampleRate) ||
-		(m_config.m_rfBandwidth != m_running.m_rfBandwidth))
+		(m_config.m_rfBandwidth != m_running.m_rfBandwidth) ||
+		(m_config.m_audioSampleRate != m_running.m_audioSampleRate))
 	{
 		m_settingsMutex.lock();
 		m_interpolator.create(16, m_config.m_inputSampleRate, m_config.m_rfBandwidth / 2.2);
@@ -191,14 +189,6 @@ void AMDemod::apply()
 		m_settingsMutex.unlock();
 	}
 
-	if((m_config.m_afBandwidth != m_running.m_afBandwidth) ||
-		(m_config.m_audioSampleRate != m_running.m_audioSampleRate))
-	{
-		m_settingsMutex.lock();
-		m_lowpass.create(21, m_config.m_audioSampleRate, m_config.m_afBandwidth);
-		m_settingsMutex.unlock();
-	}
-
 	if(m_config.m_squelch != m_running.m_squelch)
 	{
 		m_squelchLevel = pow(10.0, m_config.m_squelch / 20.0);
@@ -208,7 +198,6 @@ void AMDemod::apply()
 	m_running.m_inputSampleRate = m_config.m_inputSampleRate;
 	m_running.m_inputFrequencyOffset = m_config.m_inputFrequencyOffset;
 	m_running.m_rfBandwidth = m_config.m_rfBandwidth;
-	m_running.m_afBandwidth = m_config.m_afBandwidth;
 	m_running.m_squelch = m_config.m_squelch;
 	m_running.m_volume = m_config.m_volume;
 	m_running.m_audioSampleRate = m_config.m_audioSampleRate;

plugins/channelrx/demodam/amdemod.h

@@ -22,7 +22,6 @@
 #include <vector>
 #include "dsp/nco.h"
 #include "dsp/interpolator.h"
-#include "dsp/lowpass.h"
 #include "dsp/movingaverage.h"
 #include "dsp/agc.h"
 #include "audio/audiofifo.h"
@@ -34,7 +33,7 @@ public:
 	AMDemod();
 	~AMDemod();
 
-	void configure(MessageQueue* messageQueue, Real rfBandwidth, Real afBandwidth, Real volume, Real squelch, bool audioMute);
+	void configure(MessageQueue* messageQueue, Real rfBandwidth, Real volume, Real squelch, bool audioMute);
 
 	virtual void feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end, bool po);
 	virtual void start();
@@ -50,27 +49,24 @@ private:
 
 	public:
 		Real getRFBandwidth() const { return m_rfBandwidth; }
-		Real getAFBandwidth() const { return m_afBandwidth; }
 		Real getVolume() const { return m_volume; }
 		Real getSquelch() const { return m_squelch; }
 		bool getAudioMute() const { return m_audioMute; }
 
-		static MsgConfigureAMDemod* create(Real rfBandwidth, Real afBandwidth, Real volume, Real squelch, bool audioMute)
+		static MsgConfigureAMDemod* create(Real rfBandwidth, Real volume, Real squelch, bool audioMute)
 		{
-			return new MsgConfigureAMDemod(rfBandwidth, afBandwidth, volume, squelch, audioMute);
+			return new MsgConfigureAMDemod(rfBandwidth, volume, squelch, audioMute);
 		}
 
 	private:
 		Real m_rfBandwidth;
-		Real m_afBandwidth;
 		Real m_volume;
 		Real m_squelch;
 		bool m_audioMute;
 
-		MsgConfigureAMDemod(Real rfBandwidth, Real afBandwidth, Real volume, Real squelch, bool audioMute) :
+		MsgConfigureAMDemod(Real rfBandwidth, Real volume, Real squelch, bool audioMute) :
 			Message(),
 			m_rfBandwidth(rfBandwidth),
-			m_afBandwidth(afBandwidth),
 			m_volume(volume),
 			m_squelch(squelch),
 			m_audioMute(audioMute)
@@ -92,7 +88,6 @@ private:
 		int m_inputSampleRate;
 		qint64 m_inputFrequencyOffset;
 		Real m_rfBandwidth;
-		Real m_afBandwidth;
 		Real m_squelch;
 		Real m_volume;
 		quint32 m_audioSampleRate;
@@ -102,7 +97,6 @@ private:
 			m_inputSampleRate(-1),
 			m_inputFrequencyOffset(0),
 			m_rfBandwidth(-1),
-			m_afBandwidth(-1),
 			m_squelch(0),
 			m_volume(0),
 			m_audioSampleRate(0),
@@ -117,7 +111,6 @@ private:
 	Interpolator m_interpolator;
 	Real m_interpolatorDistance;
 	Real m_interpolatorDistanceRemain;
-	Lowpass<Real> m_lowpass;
 
 	Real m_squelchLevel;
 	int m_squelchCount;
@@ -163,8 +156,6 @@ private:
         {
             Real demod = sqrt(magsq);
 
-            demod = m_lowpass.filter(demod);
-
             if (demod < -1)
             {
                 demod = -1;

plugins/channelrx/demodam/amdemodgui.cpp

@@ -35,10 +35,6 @@
 
 const QString AMDemodGUI::m_channelID = "de.maintech.sdrangelove.channel.am";
 
-const int AMDemodGUI::m_rfBW[] = {
-	3000, 4000, 5000, 6250, 8330, 10000, 12500, 15000, 20000, 25000, 40000
-};
-
 AMDemodGUI* AMDemodGUI::create(PluginAPI* pluginAPI, DeviceSourceAPI *deviceAPI)
 {
 	AMDemodGUI* gui = new AMDemodGUI(pluginAPI, deviceAPI);
@@ -74,8 +70,7 @@ void AMDemodGUI::resetToDefaults()
 {
 	blockApplySettings(true);
 
-	ui->rfBW->setValue(4);
+	ui->rfBW->setValue(50);
-	ui->afBW->setValue(3);
 	ui->volume->setValue(20);
 	ui->squelch->setValue(-40);
 	ui->deltaFrequency->setValue(0);
@@ -89,7 +84,7 @@ QByteArray AMDemodGUI::serialize() const
 	SimpleSerializer s(1);
 	s.writeS32(1, m_channelMarker.getCenterFrequency());
 	s.writeS32(2, ui->rfBW->value());
-	s.writeS32(3, ui->afBW->value());
+	//s.writeS32(3, ui->afBW->value());
 	s.writeS32(4, ui->volume->value());
 	s.writeS32(5, ui->squelch->value());
 	s.writeU32(7, m_channelMarker.getColor().rgb());
@@ -120,7 +115,7 @@ bool AMDemodGUI::deserialize(const QByteArray& data)
 		d.readS32(2, &tmp, 4);
 		ui->rfBW->setValue(tmp);
 		d.readS32(3, &tmp, 3);
-		ui->afBW->setValue(tmp);
+		//ui->afBW->setValue(tmp);
 		d.readS32(4, &tmp, 20);
 		ui->volume->setValue(tmp);
 		d.readS32(5, &tmp, -40);
@@ -176,14 +171,8 @@ void AMDemodGUI::on_deltaFrequency_changed(quint64 value)
 
 void AMDemodGUI::on_rfBW_valueChanged(int value)
 {
-	ui->rfBWText->setText(QString("%1 kHz").arg(m_rfBW[value] / 1000.0));
+	ui->rfBWText->setText(QString("%1 kHz").arg(value / 10.0));
-	m_channelMarker.setBandwidth(m_rfBW[value]);
+	m_channelMarker.setBandwidth(value * 100);
-	applySettings();
-}
-
-void AMDemodGUI::on_afBW_valueChanged(int value)
-{
-	ui->afBWText->setText(QString("%1 kHz").arg(value));
 	applySettings();
 }
 
@@ -249,7 +238,7 @@ AMDemodGUI::AMDemodGUI(PluginAPI* pluginAPI, DeviceSourceAPI *deviceAPI, QWidget
 
 	//m_channelMarker = new ChannelMarker(this);
 	m_channelMarker.setColor(Qt::yellow);
-	m_channelMarker.setBandwidth(12500);
+	m_channelMarker.setBandwidth(5000);
 	m_channelMarker.setCenterFrequency(0);
 	m_channelMarker.setVisible(true);
 
@@ -292,8 +281,7 @@ void AMDemodGUI::applySettings()
 		ui->deltaMinus->setChecked(m_channelMarker.getCenterFrequency() < 0);
 
 		m_amDemod->configure(m_amDemod->getInputMessageQueue(),
-			m_rfBW[ui->rfBW->value()],
+			ui->rfBW->value() * 100.0,
-			ui->afBW->value() * 1000.0,
 			ui->volume->value() / 10.0,
 			ui->squelch->value(),
 			ui->audioMute->isChecked());

plugins/channelrx/demodam/amdemodgui.h

@@ -42,7 +42,6 @@ private slots:
 	void on_deltaFrequency_changed(quint64 value);
 	void on_deltaMinus_toggled(bool minus);
 	void on_rfBW_valueChanged(int value);
-	void on_afBW_valueChanged(int value);
 	void on_volume_valueChanged(int value);
 	void on_squelch_valueChanged(int value);
 	void on_audioMute_toggled(bool checked);
@@ -64,8 +63,6 @@ private:
 	MovingAverage<Real> m_channelPowerDbAvg;
 	bool m_squelchOpen;
 
-	static const int m_rfBW[];
-
 	explicit AMDemodGUI(PluginAPI* pluginAPI, DeviceSourceAPI *deviceAPI, QWidget* parent = NULL);
 	virtual ~AMDemodGUI();
 

plugins/channelrx/demodam/amdemodgui.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>257</width>
-    <height>143</height>
+    <height>131</height>
    </rect>
   </property>
   <property name="font">
@@ -28,7 +28,7 @@
      <x>10</x>
      <y>10</y>
      <width>235</width>
-     <height>121</height>
+     <height>111</height>
     </rect>
    </property>
    <property name="windowTitle">
@@ -184,14 +184,17 @@
         <property name="toolTip">
          <string>Demodulator (RF) bandwidth</string>
         </property>
-        <property name="maximum">
+        <property name="minimum">
          <number>10</number>
         </property>
+        <property name="maximum">
+         <number>200</number>
+        </property>
         <property name="pageStep">
          <number>1</number>
         </property>
         <property name="value">
-         <number>6</number>
+         <number>50</number>
         </property>
         <property name="orientation">
          <enum>Qt::Horizontal</enum>
@@ -207,56 +210,7 @@
          </size>
         </property>
         <property name="text">
-         <string>12.5kHz</string>
+         <string>5 kHz</string>
-        </property>
-        <property name="alignment">
-         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
-        </property>
-       </widget>
-      </item>
-     </layout>
-    </item>
-    <item>
-     <layout class="QHBoxLayout" name="afBandwidthLayout">
-      <item>
-       <widget class="QLabel" name="label_2">
-        <property name="text">
-         <string>AF BW</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QSlider" name="afBW">
-        <property name="toolTip">
-         <string>Audio bandwidth</string>
-        </property>
-        <property name="minimum">
-         <number>1</number>
-        </property>
-        <property name="maximum">
-         <number>20</number>
-        </property>
-        <property name="pageStep">
-         <number>1</number>
-        </property>
-        <property name="value">
-         <number>3</number>
-        </property>
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLabel" name="afBWText">
-        <property name="minimumSize">
-         <size>
-          <width>50</width>
-          <height>0</height>
-         </size>
-        </property>
-        <property name="text">
-         <string>3 kHz</string>
         </property>
         <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
@@ -398,6 +352,7 @@
   <include location="../../../sdrbase/resources/res.qrc"/>
   <include location="../../../sdrbase/resources/res.qrc"/>
   <include location="../../../sdrbase/resources/res.qrc"/>
+  <include location="../../../sdrbase/resources/res.qrc"/>
  </resources>
  <connections/>
 </ui>

plugins/channelrx/demodam/amdemodplugin.cpp

@@ -7,7 +7,7 @@
 
 const PluginDescriptor AMDemodPlugin::m_pluginDescriptor = {
 	QString("AM Demodulator"),
-	QString("2.3.1"),
+	QString("2.4.0"),
 	QString("(c) Edouard Griffiths, F4EXB"),
 	QString("https://github.com/f4exb/sdrangel"),
 	true,

plugins/channeltx/modam/ammod.h

@@ -25,7 +25,6 @@
 #include "dsp/basebandsamplesource.h"
 #include "dsp/nco.h"
 #include "dsp/interpolator.h"
-#include "dsp/lowpass.h"
 #include "dsp/movingaverage.h"
 #include "dsp/agc.h"
 #include "audio/audiofifo.h"

plugins/channeltx/modam/ammodgui.cpp

@@ -334,7 +334,7 @@ AMModGUI::AMModGUI(PluginAPI* pluginAPI, DeviceSinkAPI *deviceAPI, QWidget* pare
 
 	//m_channelMarker = new ChannelMarker(this);
 	m_channelMarker.setColor(Qt::yellow);
-	m_channelMarker.setBandwidth(12500);
+	m_channelMarker.setBandwidth(5000);
 	m_channelMarker.setCenterFrequency(0);
 	m_channelMarker.setVisible(true);