plugins/channelrx/remotesink/remotesinksender.cpp

@@ -85,6 +85,7 @@ void RemoteSinkSender::sendDataBlock(RemoteDataBlock *dataBlock)
 
     uint16_t frameIndex = dataBlock->m_txControlBlock.m_frameIndex;
     int nbBlocksFEC = dataBlock->m_txControlBlock.m_nbBlocksFEC;
+    int txDelay = dataBlock->m_txControlBlock.m_txDelay;
     m_address.setAddress(dataBlock->m_txControlBlock.m_dataAddress);
     uint16_t dataPort = dataBlock->m_txControlBlock.m_dataPort;
     RemoteSuperBlock *txBlockx = dataBlock->m_superBlocks;
@@ -93,8 +94,11 @@ void RemoteSinkSender::sendDataBlock(RemoteDataBlock *dataBlock)
     {
         if (m_socket)
         {
-            for (int i = 0; i < RemoteNbOrginalBlocks; i++) { // send block via UDP
+            for (int i = 0; i < RemoteNbOrginalBlocks; i++)
+            {
+                // send block via UDP
                 m_socket->writeDatagram((const char*)&txBlockx[i], (qint64 ) RemoteUdpSize, m_address, dataPort);
+                std::this_thread::sleep_for(std::chrono::microseconds(txDelay));
             }
         }
     }
@@ -135,8 +139,11 @@ void RemoteSinkSender::sendDataBlock(RemoteDataBlock *dataBlock)
         // Transmit all blocks
         if (m_socket)
         {
-            for (int i = 0; i < cm256Params.OriginalCount + cm256Params.RecoveryCount; i++) { // send block via UDP
+            for (int i = 0; i < cm256Params.OriginalCount + cm256Params.RecoveryCount; i++)
+            {
+                // send block via UDP
                 m_socket->writeDatagram((const char*)&txBlockx[i], (qint64 ) RemoteUdpSize, m_address, dataPort);
+                std::this_thread::sleep_for(std::chrono::microseconds(txDelay));
             }
         }
     }

plugins/channelrx/remotesink/remotesinksink.cpp

@@ -36,6 +36,7 @@ RemoteSinkSink::RemoteSinkSink() :
         m_frequencyOffset(0),
         m_basebandSampleRate(48000),
         m_nbBlocksFEC(0),
+        m_txDelay(35),
         m_dataAddress("127.0.0.1"),
         m_dataPort(9090)
 {
@@ -164,6 +165,7 @@ void RemoteSinkSink::feed(const SampleVector::const_iterator& begin, const Sampl
                 m_dataBlock->m_txControlBlock.m_processed = false;
                 m_dataBlock->m_txControlBlock.m_complete = true;
                 m_dataBlock->m_txControlBlock.m_nbBlocksFEC = m_nbBlocksFEC;
+                m_dataBlock->m_txControlBlock.m_txDelay = m_txDelay;
                 m_dataBlock->m_txControlBlock.m_dataAddress = m_dataAddress;
                 m_dataBlock->m_txControlBlock.m_dataPort = m_dataPort;
 

plugins/channelrx/remotesink/remotesinksink.h

@@ -61,6 +61,7 @@ private:
     int64_t m_frequencyOffset;
     uint32_t m_basebandSampleRate;
     int m_nbBlocksFEC;
+    int m_txDelay;
     QString m_dataAddress;
     uint16_t m_dataPort;
 

plugins/channeltx/remotesource/remotesourcegui.cpp

@@ -330,9 +330,12 @@ void RemoteSourceGUI::on_dataPort_returnPressed()
     bool dataOk;
     int dataPort = ui->dataPort->text().toInt(&dataOk);
 
-    if ((!dataOk) || (dataPort < 1024) || (dataPort > 65535)) {
+    if((!dataOk) || (dataPort < 1024) || (dataPort > 65535))
+    {
         return;
-    } else {
+    }
+    else
+    {
         m_settings.m_dataPort = dataPort;
     }
 
@@ -347,7 +350,8 @@ void RemoteSourceGUI::on_dataApplyButton_clicked(bool checked)
     bool dataOk;
     int udpDataPort = ui->dataPort->text().toInt(&dataOk);
 
-    if ((dataOk) && (udpDataPort >= 1024) && (udpDataPort < 65535)) {
+    if((dataOk) && (udpDataPort >= 1024) && (udpDataPort < 65535))
+    {
         m_settings.m_dataPort = udpDataPort;
     }
 

plugins/channeltx/remotesource/remotesourcegui.ui

@@ -139,7 +139,7 @@
        </spacer>
       </item>
       <item>
-       <widget class="QPushButton" name="dataApplyButton">
+       <widget class="QPushButton" name="pushButton">
         <property name="maximumSize">
          <size>
           <width>30</width>

plugins/channeltx/remotesource/remotesourcesource.cpp

@@ -35,9 +35,7 @@ RemoteSourceSource::RemoteSourceSource() :
 }
 
 RemoteSourceSource::~RemoteSourceSource()
-{
-    stop();
-}
+{}
 
 void RemoteSourceSource::pull(SampleVector::iterator begin, unsigned int nbSamples)
 {
@@ -107,7 +105,7 @@ void RemoteSourceSource::stop()
     {
         stopWorker();
         m_sourceWorker->deleteLater();
-        m_sourceWorker = nullptr;
+        m_sourceWorker = 0;
     }
 
     m_running = false;
@@ -278,4 +276,4 @@ void RemoteSourceSource::applyChannelSettings(int channelSampleRate, bool force)
     }
 
     m_channelSampleRate = channelSampleRate;
-}
+}

plugins/channeltx/remotesource/remotesourceworker.cpp

@@ -19,9 +19,9 @@
 #include <channel/remotedataqueue.h>
 #include <algorithm>
 
-#include <QThread>
-
+#include <QUdpSocket>
 #include "cm256cc/cm256.h"
+
 #include "remotesourceworker.h"
 
 MESSAGE_CLASS_DEFINITION(RemoteSourceWorker::MsgDataBind, Message)
@@ -31,18 +31,10 @@ RemoteSourceWorker::RemoteSourceWorker(RemoteDataQueue *dataQueue, QObject* pare
     m_running(false),
     m_dataQueue(dataQueue),
     m_address(QHostAddress::LocalHost),
-    m_socket(this),
-    m_mutex(QMutex::Recursive),
-    m_sampleRate(0)
+    m_socket(nullptr)
 {
     std::fill(m_dataBlocks, m_dataBlocks+4, (RemoteDataBlock *) 0);
     connect(&m_inputMessageQueue, SIGNAL(messageEnqueued()), this, SLOT(handleInputMessages()), Qt::QueuedConnection);
-    connect(&m_socket, SIGNAL(readyRead()),this, SLOT(recv()));
-#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
-    connect(&m_socket, QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error), this, &APRSWorker::errorOccurred);
-#else
-    connect(&m_socket, &QAbstractSocket::errorOccurred, this, &RemoteSourceWorker::errorOccurred);
-#endif
 }
 
 RemoteSourceWorker::~RemoteSourceWorker()
@@ -56,43 +48,19 @@ void RemoteSourceWorker::dataBind(const QString& address, uint16_t port)
     m_inputMessageQueue.push(msg);
 }
 
-bool RemoteSourceWorker::startWork()
+void RemoteSourceWorker::startWork()
 {
     qDebug("RemoteSourceWorker::startWork");
-    QMutexLocker mutexLocker(&m_mutex);
-    m_socket.setSocketOption(QAbstractSocket::ReceiveBufferSizeSocketOption, getDataSocketBufferSize(m_sampleRate));
-    connect(&m_inputMessageQueue, SIGNAL(messageEnqueued()), this, SLOT(handleInputMessages()));
-    connect(thread(), SIGNAL(started()), this, SLOT(started()));
-    connect(thread(), SIGNAL(finished()), this, SLOT(finished()));
-    m_running = true;
-    return m_running;
-}
-
-void RemoteSourceWorker::started()
-{
-    disconnect(thread(), SIGNAL(started()), this, SLOT(started()));
+    m_socket = new QUdpSocket(this);
+    m_running = false;
 }
 
 void RemoteSourceWorker::stopWork()
 {
     qDebug("RemoteSourceWorker::stopWork");
-    QMutexLocker mutexLocker(&m_mutex);
-    disconnect(&m_inputMessageQueue, SIGNAL(messageEnqueued()), this, SLOT(handleInputMessages()));
-}
-
-void RemoteSourceWorker::finished()
-{
-    // Close any existing connection
-    if (m_socket.isOpen()) {
-        m_socket.close();
-    }
+    delete m_socket;
+    m_socket = nullptr;
     m_running = false;
-    disconnect(thread(), SIGNAL(finished()), this, SLOT(finished()));
-}
-
-void RemoteSourceWorker::errorOccurred(QAbstractSocket::SocketError socketError)
-{
-    qWarning() << "RemoteSourceWorker::errorOccurred: " << socketError;
 }
 
 void RemoteSourceWorker::handleInputMessages()
@@ -103,12 +71,15 @@ void RemoteSourceWorker::handleInputMessages()
     {
         if (MsgDataBind::match(*message))
         {
-            QMutexLocker mutexLocker(&m_mutex);
             MsgDataBind* notif = (MsgDataBind*) message;
             qDebug("RemoteSourceWorker::handleInputMessages: MsgDataBind: %s:%d", qPrintable(notif->getAddress().toString()), notif->getPort());
-            disconnect(&m_socket, SIGNAL(readyRead()), this, SLOT(readPendingDatagrams()));
-            m_socket.bind(notif->getAddress(), notif->getPort());
-            connect(&m_socket, SIGNAL(readyRead()), this, SLOT(readPendingDatagrams()));
+
+            if (m_socket)
+            {
+                disconnect(m_socket, SIGNAL(readyRead()), this, SLOT(readPendingDatagrams()));
+                m_socket->bind(notif->getAddress(), notif->getPort());
+                connect(m_socket, SIGNAL(readyRead()), this, SLOT(readPendingDatagrams()));
+            }
         }
     }
 }
@@ -118,30 +89,16 @@ void RemoteSourceWorker::readPendingDatagrams()
     RemoteSuperBlock superBlock;
     qint64 size;
 
-    while (m_socket.hasPendingDatagrams())
+    while (m_socket->hasPendingDatagrams())
     {
         QHostAddress sender;
         quint16 senderPort = 0;
         //qint64 pendingDataSize = m_socket->pendingDatagramSize();
-        size = m_socket.readDatagram((char *) &superBlock, (long long int) sizeof(RemoteSuperBlock), &sender, &senderPort);
+        size = m_socket->readDatagram((char *) &superBlock, (long long int) sizeof(RemoteSuperBlock), &sender, &senderPort);
 
         if (size == sizeof(RemoteSuperBlock))
         {
             unsigned int dataBlockIndex = superBlock.m_header.m_frameIndex % m_nbDataBlocks;
-            int blockIndex = superBlock.m_header.m_blockIndex;
-
-            if (blockIndex == 0) // first block with meta data
-            {
-                const RemoteMetaDataFEC *metaData = (const RemoteMetaDataFEC *) &superBlock.m_protectedBlock;
-                uint32_t sampleRate = metaData->m_sampleRate;
-
-                if (m_sampleRate != sampleRate)
-                {
-                    qDebug("RemoteSourceWorker::readPendingDatagrams: sampleRate: %u", sampleRate);
-                    m_socket.setSocketOption(QAbstractSocket::ReceiveBufferSizeSocketOption, getDataSocketBufferSize(sampleRate));
-                    m_sampleRate = sampleRate;
-                }
-            }
 
             // create the first block for this index
             if (m_dataBlocks[dataBlockIndex] == 0) {
@@ -188,12 +145,3 @@ void RemoteSourceWorker::readPendingDatagrams()
     }
 }
 
-int RemoteSourceWorker::getDataSocketBufferSize(uint32_t inSampleRate)
-{
-    // set a floor value at 24 kS/s
-    uint32_t samplerate = inSampleRate < 24000 ? 24000 : inSampleRate;
-    // 250 ms (1/4s) at current sample rate
-    int bufferSize = (samplerate * 2 * (SDR_RX_SAMP_SZ == 16 ? 2 : 4)) / 4;
-    qDebug("RemoteSourceWorker::getDataSocketBufferSize: %d bytes", bufferSize);
-    return bufferSize;
-}

plugins/channeltx/remotesource/remotesourceworker.h

@@ -20,13 +20,13 @@
 
 #include <QObject>
 #include <QHostAddress>
-#include <QUdpSocket>
 
 #include "util/message.h"
 #include "util/messagequeue.h"
 
 class RemoteDataQueue;
 class RemoteDataBlock;
+class QUdpSocket;
 
 class RemoteSourceWorker : public QObject {
     Q_OBJECT
@@ -57,7 +57,7 @@ public:
     RemoteSourceWorker(RemoteDataQueue *dataQueue, QObject* parent = 0);
     ~RemoteSourceWorker();
 
-    bool startWork();
+    void startWork();
     void stopWork();
     void dataBind(const QString& address, uint16_t port);
 
@@ -68,19 +68,12 @@ private:
     RemoteDataQueue *m_dataQueue;
 
     QHostAddress m_address;
-    QUdpSocket m_socket;
-    QMutex m_mutex;
+    QUdpSocket *m_socket;
 
-    static const uint32_t m_nbDataBlocks = 4;       //!< number of data blocks in the ring buffer
+    static const uint32_t m_nbDataBlocks = 4;          //!< number of data blocks in the ring buffer
     RemoteDataBlock *m_dataBlocks[m_nbDataBlocks];  //!< ring buffer of data blocks indexed by frame affinity
-    uint32_t m_sampleRate;                          //!< current sample rate from meta data
-
-    static int getDataSocketBufferSize(uint32_t inSampleRate);
 
 private slots:
-    void started();
-    void finished();
-    void errorOccurred(QAbstractSocket::SocketError socketError);
     void handleInputMessages();
     void readPendingDatagrams();
 };

plugins/samplesink/remoteoutput/remoteoutput.cpp

@@ -100,6 +100,8 @@ bool RemoteOutput::start()
 	m_lastQueueLength = -2; // set first value out of bounds
 	m_chunkSizeCorrection = 0;
 
+    m_remoteOutputWorker->setTxDelay(m_settings.m_txDelay);
+
 	mutexLocker.unlock();
 	//applySettings(m_generalSettings, m_settings, true);
 	qDebug("RemoteOutput::start: started");
@@ -258,6 +260,7 @@ void RemoteOutput::applySettings(const RemoteOutputSettings& settings, bool forc
 {
     QMutexLocker mutexLocker(&m_mutex);
     bool forwardChange = false;
+    bool changeTxDelay = false;
     QList<QString> reverseAPIKeys;
 
     if ((m_settings.m_dataAddress != settings.m_dataAddress) || force) {
@@ -292,6 +295,7 @@ void RemoteOutput::applySettings(const RemoteOutputSettings& settings, bool forc
         m_tickMultiplier = m_tickMultiplier < 20 ? 20 : m_tickMultiplier; // not below half a second
 
         forwardChange = true;
+        changeTxDelay = true;
     }
 
     if (force || (m_settings.m_nbFECBlocks != settings.m_nbFECBlocks))
@@ -301,12 +305,28 @@ void RemoteOutput::applySettings(const RemoteOutputSettings& settings, bool forc
         if (m_remoteOutputWorker != 0) {
             m_remoteOutputWorker->setNbBlocksFEC(settings.m_nbFECBlocks);
         }
+
+        changeTxDelay = true;
+    }
+
+    if (force || (m_settings.m_txDelay != settings.m_txDelay))
+    {
+        reverseAPIKeys.append("txDelay");
+        changeTxDelay = true;
+    }
+
+    if (changeTxDelay)
+    {
+        if (m_remoteOutputWorker != 0) {
+            m_remoteOutputWorker->setTxDelay(settings.m_txDelay);
+        }
     }
 
     mutexLocker.unlock();
 
     qDebug() << "RemoteOutput::applySettings:"
             << " m_sampleRate: " << settings.m_sampleRate
+            << " m_txDelay: " << settings.m_txDelay
             << " m_nbFECBlocks: " << settings.m_nbFECBlocks
             << " m_apiAddress: " << settings.m_apiAddress
             << " m_apiPort: " << settings.m_apiPort
@@ -401,6 +421,9 @@ void RemoteOutput::webapiUpdateDeviceSettings(
     if (deviceSettingsKeys.contains("sampleRate")) {
         settings.m_sampleRate = response.getRemoteOutputSettings()->getSampleRate();
     }
+    if (deviceSettingsKeys.contains("txDelay")) {
+        settings.m_txDelay = response.getRemoteOutputSettings()->getTxDelay();
+    }
     if (deviceSettingsKeys.contains("nbFECBlocks")) {
         settings.m_nbFECBlocks = response.getRemoteOutputSettings()->getNbFecBlocks();
     }
@@ -451,6 +474,7 @@ void RemoteOutput::webapiFormatDeviceSettings(SWGSDRangel::SWGDeviceSettings& re
 {
     response.getRemoteOutputSettings()->setCenterFrequency(settings.m_centerFrequency);
     response.getRemoteOutputSettings()->setSampleRate(settings.m_sampleRate);
+    response.getRemoteOutputSettings()->setTxDelay(settings.m_txDelay);
     response.getRemoteOutputSettings()->setNbFecBlocks(settings.m_nbFECBlocks);
     response.getRemoteOutputSettings()->setApiAddress(new QString(settings.m_apiAddress));
     response.getRemoteOutputSettings()->setApiPort(settings.m_apiPort);
@@ -635,6 +659,9 @@ void RemoteOutput::webapiReverseSendSettings(QList<QString>& deviceSettingsKeys,
     if (deviceSettingsKeys.contains("sampleRate") || force) {
         swgRemoteOutputSettings->setSampleRate(settings.m_sampleRate);
     }
+    if (deviceSettingsKeys.contains("txDelay") || force) {
+        swgRemoteOutputSettings->setTxDelay(settings.m_txDelay);
+    }
     if (deviceSettingsKeys.contains("nbFECBlocks") || force) {
         swgRemoteOutputSettings->setNbFecBlocks(settings.m_nbFECBlocks);
     }

plugins/samplesink/remoteoutput/remoteoutputgui.cpp

@@ -211,11 +211,20 @@ void RemoteOutputSinkGui::updateSampleRate()
     ui->deviceRateText->setText(tr("%1k").arg((float)(m_sampleRate) / 1000));
 }
 
+void RemoteOutputSinkGui::updateTxDelayTooltip()
+{
+    int samplesPerBlock = RemoteNbBytesPerBlock / (SDR_RX_SAMP_SZ <= 16 ? 4 : 8);
+    double delay = ((127*samplesPerBlock*m_settings.m_txDelay) / m_settings.m_sampleRate)/(128 + m_settings.m_nbFECBlocks);
+    ui->txDelayText->setToolTip(tr("%1 us").arg(QString::number(delay*1e6, 'f', 0)));
+}
+
 void RemoteOutputSinkGui::displaySettings()
 {
     blockApplySettings(true);
     ui->centerFrequency->setValue(m_deviceCenterFrequency / 1000);
     ui->sampleRate->setValue(m_settings.m_sampleRate);
+    ui->txDelay->setValue(m_settings.m_txDelay*100);
+    ui->txDelayText->setText(tr("%1").arg(m_settings.m_txDelay*100));
     ui->nbFECBlocks->setValue(m_settings.m_nbFECBlocks);
 
     QString s0 = QString::number(128 + m_settings.m_nbFECBlocks, 'f', 0);
@@ -279,6 +288,15 @@ void RemoteOutputSinkGui::updateStatus()
 void RemoteOutputSinkGui::on_sampleRate_changed(quint64 value)
 {
     m_settings.m_sampleRate = value;
+    updateTxDelayTooltip();
+    sendSettings();
+}
+
+void RemoteOutputSinkGui::on_txDelay_valueChanged(int value)
+{
+    m_settings.m_txDelay = value / 100.0;
+    ui->txDelayText->setText(tr("%1").arg(value));
+    updateTxDelayTooltip();
     sendSettings();
 }
 
@@ -290,6 +308,7 @@ void RemoteOutputSinkGui::on_nbFECBlocks_valueChanged(int value)
     QString s = QString::number(nbOriginalBlocks + nbFECBlocks, 'f', 0);
     QString s1 = QString::number(nbFECBlocks, 'f', 0);
     ui->nominalNbBlocksText->setText(tr("%1/%2").arg(s).arg(s1));
+    updateTxDelayTooltip();
     sendSettings();
 }
 

plugins/samplesink/remoteoutput/remoteoutputgui.h

@@ -124,6 +124,7 @@ private:
     void sendControl(bool force = false);
 	void sendSettings();
 	void updateSampleRate();
+	void updateTxDelayTooltip();
 	void displayEventCounts();
 	void displayEventStatus(int recoverableCount, int unrecoverableCount);
     void displayEventTimer();
@@ -133,6 +134,7 @@ private:
 private slots:
     void handleInputMessages();
     void on_sampleRate_changed(quint64 value);
+    void on_txDelay_valueChanged(int value);
     void on_nbFECBlocks_valueChanged(int value);
     void on_deviceIndex_returnPressed();
     void on_channelIndex_returnPressed();

plugins/samplesink/remoteoutput/remoteoutputgui.ui

@@ -249,6 +249,60 @@
        </property>
       </widget>
      </item>
+     <item>
+      <widget class="QLabel" name="txDelayLabel">
+       <property name="text">
+        <string>UDly</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QDial" name="txDelay">
+       <property name="maximumSize">
+        <size>
+         <width>24</width>
+         <height>24</height>
+        </size>
+       </property>
+       <property name="toolTip">
+        <string>Delay between consecutive UDP packets in percentage of nominal UDP packet process time</string>
+       </property>
+       <property name="minimum">
+        <number>10</number>
+       </property>
+       <property name="maximum">
+        <number>90</number>
+       </property>
+       <property name="pageStep">
+        <number>1</number>
+       </property>
+       <property name="value">
+        <number>50</number>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QLabel" name="txDelayText">
+       <property name="minimumSize">
+        <size>
+         <width>20</width>
+         <height>0</height>
+        </size>
+       </property>
+       <property name="maximumSize">
+        <size>
+         <width>20</width>
+         <height>16777215</height>
+        </size>
+       </property>
+       <property name="text">
+        <string>90</string>
+       </property>
+       <property name="alignment">
+        <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+       </property>
+      </widget>
+     </item>
      <item>
       <spacer name="horizontalSpacer">
        <property name="orientation">

plugins/samplesink/remoteoutput/remoteoutputsender.cpp

@@ -22,6 +22,8 @@
 ///////////////////////////////////////////////////////////////////////////////////
 
 
+#include <thread>
+#include <chrono>
 #include <boost/crc.hpp>
 #include <boost/cstdint.hpp>
 
@@ -91,6 +93,7 @@ void RemoteOutputSender::sendDataBlock(RemoteDataBlock *dataBlock)
 
     uint16_t frameIndex = dataBlock->m_txControlBlock.m_frameIndex;
     int nbBlocksFEC = dataBlock->m_txControlBlock.m_nbBlocksFEC;
+    int txDelay = dataBlock->m_txControlBlock.m_txDelay;
     m_remoteHostAddress.setAddress(dataBlock->m_txControlBlock.m_dataAddress);
     uint16_t dataPort = dataBlock->m_txControlBlock.m_dataPort;
     RemoteSuperBlock *txBlockx = dataBlock->m_superBlocks;
@@ -99,8 +102,11 @@ void RemoteOutputSender::sendDataBlock(RemoteDataBlock *dataBlock)
     {
         if (m_udpSocket)
         {
-            for (int i = 0; i < RemoteNbOrginalBlocks; i++) { // send block via UDP
+            for (int i = 0; i < RemoteNbOrginalBlocks; i++)
+            {
+                // send block via UDP
                 m_udpSocket->writeDatagram((const char*)&txBlockx[i], (qint64 ) RemoteUdpSize, m_remoteHostAddress, dataPort);
+                std::this_thread::sleep_for(std::chrono::microseconds(txDelay));
             }
         }
     }
@@ -146,8 +152,11 @@ void RemoteOutputSender::sendDataBlock(RemoteDataBlock *dataBlock)
         // Transmit all blocks
         if (m_udpSocket)
         {
-            for (int i = 0; i < cm256Params.OriginalCount + cm256Params.RecoveryCount; i++) { // send block via UDP
+            for (int i = 0; i < cm256Params.OriginalCount + cm256Params.RecoveryCount; i++)
+            {
+                // send block via UDP
                 m_udpSocket->writeDatagram((const char*)&txBlockx[i], (qint64 ) RemoteUdpSize, m_remoteHostAddress, dataPort);
+                std::this_thread::sleep_for(std::chrono::microseconds(txDelay));
             }
         }
     }

plugins/samplesink/remoteoutput/remoteoutputsettings.cpp

@@ -27,6 +27,7 @@ void RemoteOutputSettings::resetToDefaults()
 {
     m_centerFrequency = 435000*1000;
     m_sampleRate = 48000;
+    m_txDelay = 0.35;
     m_nbFECBlocks = 0;
     m_apiAddress = "127.0.0.1";
     m_apiPort = 9091;
@@ -46,6 +47,7 @@ QByteArray RemoteOutputSettings::serialize() const
 
     s.writeU64(1, m_centerFrequency);
     s.writeU32(2, m_sampleRate);
+    s.writeFloat(3, m_txDelay);
     s.writeU32(4, m_nbFECBlocks);
     s.writeString(5, m_apiAddress);
     s.writeU32(6, m_apiPort);
@@ -77,6 +79,7 @@ bool RemoteOutputSettings::deserialize(const QByteArray& data)
 
         d.readU64(1, &m_centerFrequency, 435000*1000);
         d.readU32(2, &m_sampleRate, 48000);
+        d.readFloat(3, &m_txDelay, 0.5);
         d.readU32(4, &m_nbFECBlocks, 0);
         d.readString(5, &m_apiAddress, "127.0.0.1");
         d.readU32(6, &uintval, 9090);

plugins/samplesink/remoteoutput/remoteoutputsettings.h

@@ -24,6 +24,7 @@
 struct RemoteOutputSettings {
     quint64 m_centerFrequency;
     quint32 m_sampleRate;
+    float   m_txDelay;
     quint32 m_nbFECBlocks;
     QString m_apiAddress;
     quint16 m_apiPort;

plugins/samplesink/remoteoutput/remoteoutputworker.h

@@ -49,6 +49,7 @@ public:
 
 	void setSamplerate(int samplerate);
     void setNbBlocksFEC(uint32_t nbBlocksFEC) { m_udpSinkFEC.setNbBlocksFEC(nbBlocksFEC); };
+    void setTxDelay(float txDelay) { m_udpSinkFEC.setTxDelay(txDelay); };
     void setDataAddress(const QString& address, uint16_t port) { m_udpSinkFEC.setRemoteAddress(address, port); }
 
     bool isRunning() const { return m_running; }

plugins/samplesink/remoteoutput/udpsinkfec.cpp

@@ -32,6 +32,7 @@ UDPSinkFEC::UDPSinkFEC() :
     m_nbSamples(0),
     m_nbBlocksFEC(0),
     m_txDelayRatio(0.0),
+    m_txDelay(0),
     m_dataBlock(nullptr),
     m_txBlockIndex(0),
     m_txBlocksIndex(0),
@@ -70,16 +71,35 @@ void UDPSinkFEC::stopSender()
 	m_senderThread->wait();
 }
 
+void UDPSinkFEC::setTxDelay(float txDelayRatio)
+{
+    // delay is calculated from the fraction of the nominal UDP block process time
+    // frame size: 127 * (126 or 63 samples depending on I or Q sample bytes of 2 or 4 bytes respectively)
+    // divided by sample rate gives the frame process time
+    // divided by the number of actual blocks including FEC blocks gives the block (i.e. UDP block) process time
+    m_txDelayRatio = txDelayRatio;
+    int samplesPerBlock = RemoteNbBytesPerBlock / sizeof(Sample);
+    double delay = m_sampleRate == 0 ? 1.0 : (127*samplesPerBlock*txDelayRatio) / m_sampleRate;
+    delay /= 128 + m_nbBlocksFEC;
+    m_txDelay = delay * 1e6;
+    qDebug() << "UDPSinkFEC::setTxDelay:"
+        << "txDelay:" << txDelayRatio
+        << "m_txDelay:" << m_txDelay << " us"
+        << "m_sampleRate:" << m_sampleRate;
+}
+
 void UDPSinkFEC::setNbBlocksFEC(uint32_t nbBlocksFEC)
 {
     qDebug() << "UDPSinkFEC::setNbBlocksFEC: nbBlocksFEC: " << nbBlocksFEC;
     m_nbBlocksFEC = nbBlocksFEC;
+    setTxDelay(m_txDelayRatio);
 }
 
 void UDPSinkFEC::setSampleRate(uint32_t sampleRate)
 {
     qDebug() << "UDPSinkFEC::setSampleRate: sampleRate: " << sampleRate;
     m_sampleRate = sampleRate;
+    setTxDelay(m_txDelayRatio);
 }
 
 void UDPSinkFEC::setRemoteAddress(const QString& address, uint16_t port)
@@ -180,6 +200,7 @@ void UDPSinkFEC::write(const SampleVector::iterator& begin, uint32_t sampleChunk
                 m_dataBlock->m_txControlBlock.m_processed = false;
                 m_dataBlock->m_txControlBlock.m_complete = true;
                 m_dataBlock->m_txControlBlock.m_nbBlocksFEC = m_nbBlocksFEC;
+                m_dataBlock->m_txControlBlock.m_txDelay = m_txDelay;
                 m_dataBlock->m_txControlBlock.m_dataAddress = m_remoteAddress;
                 m_dataBlock->m_txControlBlock.m_dataPort = m_remotePort;
 

plugins/samplesink/remoteoutput/udpsinkfec.h

@@ -67,6 +67,7 @@ public:
     void setSampleRate(uint32_t sampleRate);
 
     void setNbBlocksFEC(uint32_t nbBlocksFEC);
+    void setTxDelay(float txDelayRatio);
     void setRemoteAddress(const QString& address, uint16_t port);
 
     /** Return true if the stream is OK, return false if there is an error. */
@@ -86,6 +87,7 @@ private:
     RemoteMetaDataFEC m_currentMetaFEC;  //!< Meta data for current frame
     uint32_t m_nbBlocksFEC;                 //!< Variable number of FEC blocks
     float m_txDelayRatio;                   //!< Delay in ratio of nominal frame period
+    uint32_t m_txDelay;                     //!< Delay in microseconds (usleep) between each sending of an UDP datagram
     RemoteDataBlock *m_dataBlock;
     RemoteSuperBlock m_superBlock;       //!< current super block being built
     int m_txBlockIndex;                     //!< Current index in blocks to transmit in the Tx row

plugins/samplesource/localinput/localinputgui.cpp

@@ -68,7 +68,8 @@ LocalInputGui::LocalInputGui(DeviceUISet *deviceUISet, QWidget* parent) :
 	m_countUnrecoverable(0),
 	m_countRecovered(0),
     m_doApplySettings(true),
-    m_forceSettings(true)
+    m_forceSettings(true),
+    m_txDelay(0.0)
 {
     m_paletteGreenText.setColor(QPalette::WindowText, Qt::green);
     m_paletteWhiteText.setColor(QPalette::WindowText, Qt::white);

plugins/samplesource/localinput/localinputgui.h

@@ -92,6 +92,7 @@ private:
 
 	bool m_doApplySettings;
     bool m_forceSettings;
+    double m_txDelay;
 
     QPalette m_paletteGreenText;
     QPalette m_paletteWhiteText;

plugins/samplesource/remoteinput/remoteinputgui.cpp

@@ -68,7 +68,8 @@ RemoteInputGui::RemoteInputGui(DeviceUISet *deviceUISet, QWidget* parent) :
 	m_countUnrecoverable(0),
 	m_countRecovered(0),
     m_doApplySettings(true),
-    m_forceSettings(true)
+    m_forceSettings(true),
+    m_txDelay(0.0)
 {
     m_paletteGreenText.setColor(QPalette::WindowText, Qt::green);
     m_paletteWhiteText.setColor(QPalette::WindowText, Qt::white);

plugins/samplesource/remoteinput/remoteinputgui.h

@@ -94,6 +94,7 @@ private:
 
 	bool m_doApplySettings;
     bool m_forceSettings;
+    double m_txDelay;
 
     QPalette m_paletteGreenText;
     QPalette m_paletteWhiteText;

scriptsapi/Readme.md

@@ -177,6 +177,7 @@ Example of a JSON file (delay is an example you normally do not need it):
               "reverseAPIPort": 8888,
               "rgbColor": -7601148,
               "title": "Channel 0",
+              "txDelay": 0,
               "useReverseAPI": 0
             },
             "channelType": "RemoteSink",

sdrbase/channel/remotedatablock.h

@@ -126,15 +126,16 @@ struct RemoteTxControlBlock
     bool m_processed;
     uint16_t m_frameIndex;
     int m_nbBlocksFEC;
+    int m_txDelay;
     QString m_dataAddress;
     uint16_t m_dataPort;
 
-    RemoteTxControlBlock()
-    {
+    RemoteTxControlBlock() {
         m_complete = false;
         m_processed = false;
         m_frameIndex = 0;
         m_nbBlocksFEC = 0;
+        m_txDelay = 100;
         m_dataAddress = "127.0.0.1";
         m_dataPort = 9090;
     }

sdrbase/resources/webapi/doc/html2/index.html

@@ -9841,6 +9841,11 @@ margin-bottom: 20px;
     "sampleRate" : {
       "type" : "integer"
     },
+    "txDelay" : {
+      "type" : "number",
+      "format" : "float",
+      "description" : "minimum delay in ms between two consecutive packets sending"
+    },
     "nbFECBlocks" : {
       "type" : "integer"
     },
@@ -51596,7 +51601,7 @@ except ApiException as e:
           </div>
           <div id="generator">
             <div class="content">
-              Generated 2021-12-07T06:38:29.681+01:00
+              Generated 2021-12-04T20:19:18.225+01:00
             </div>
           </div>
       </div>

sdrbase/resources/webapi/doc/swagger/include/RemoteOutput.yaml

@@ -6,6 +6,10 @@ RemoteOutputSettings:
       format: int64
     sampleRate:
       type: integer
+    txDelay:
+      description: minimum delay in ms between two consecutive packets sending
+      type: number
+      format: float
     nbFECBlocks:
       type: integer
     apiAddress:

swagger/sdrangel/api/swagger/include/RemoteOutput.yaml

@@ -6,6 +6,10 @@ RemoteOutputSettings:
       format: int64
     sampleRate:
       type: integer
+    txDelay:
+      description: minimum delay in ms between two consecutive packets sending
+      type: number
+      format: float
     nbFECBlocks:
       type: integer
     apiAddress:

swagger/sdrangel/code/html2/index.html

@@ -9841,6 +9841,11 @@ margin-bottom: 20px;
     "sampleRate" : {
       "type" : "integer"
     },
+    "txDelay" : {
+      "type" : "number",
+      "format" : "float",
+      "description" : "minimum delay in ms between two consecutive packets sending"
+    },
     "nbFECBlocks" : {
       "type" : "integer"
     },
@@ -51596,7 +51601,7 @@ except ApiException as e:
           </div>
           <div id="generator">
             <div class="content">
-              Generated 2021-12-07T06:38:29.681+01:00
+              Generated 2021-12-04T20:19:18.225+01:00
             </div>
           </div>
       </div>

swagger/sdrangel/code/qt5/client/SWGRemoteOutputSettings.cpp

@@ -32,6 +32,8 @@ SWGRemoteOutputSettings::SWGRemoteOutputSettings() {
     m_center_frequency_isSet = false;
     sample_rate = 0;
     m_sample_rate_isSet = false;
+    tx_delay = 0.0f;
+    m_tx_delay_isSet = false;
     nb_fec_blocks = 0;
     m_nb_fec_blocks_isSet = false;
     api_address = nullptr;
@@ -66,6 +68,8 @@ SWGRemoteOutputSettings::init() {
     m_center_frequency_isSet = false;
     sample_rate = 0;
     m_sample_rate_isSet = false;
+    tx_delay = 0.0f;
+    m_tx_delay_isSet = false;
     nb_fec_blocks = 0;
     m_nb_fec_blocks_isSet = false;
     api_address = new QString("");
@@ -95,6 +99,7 @@ SWGRemoteOutputSettings::cleanup() {
 
 
 
+
     if(api_address != nullptr) { 
         delete api_address;
     }
@@ -128,6 +133,8 @@ SWGRemoteOutputSettings::fromJsonObject(QJsonObject &pJson) {
     
     ::SWGSDRangel::setValue(&sample_rate, pJson["sampleRate"], "qint32", "");
     
+    ::SWGSDRangel::setValue(&tx_delay, pJson["txDelay"], "float", "");
+    
     ::SWGSDRangel::setValue(&nb_fec_blocks, pJson["nbFECBlocks"], "qint32", "");
     
     ::SWGSDRangel::setValue(&api_address, pJson["apiAddress"], "QString", "QString");
@@ -172,6 +179,9 @@ SWGRemoteOutputSettings::asJsonObject() {
     if(m_sample_rate_isSet){
         obj->insert("sampleRate", QJsonValue(sample_rate));
     }
+    if(m_tx_delay_isSet){
+        obj->insert("txDelay", QJsonValue(tx_delay));
+    }
     if(m_nb_fec_blocks_isSet){
         obj->insert("nbFECBlocks", QJsonValue(nb_fec_blocks));
     }
@@ -229,6 +239,16 @@ SWGRemoteOutputSettings::setSampleRate(qint32 sample_rate) {
     this->m_sample_rate_isSet = true;
 }
 
+float
+SWGRemoteOutputSettings::getTxDelay() {
+    return tx_delay;
+}
+void
+SWGRemoteOutputSettings::setTxDelay(float tx_delay) {
+    this->tx_delay = tx_delay;
+    this->m_tx_delay_isSet = true;
+}
+
 qint32
 SWGRemoteOutputSettings::getNbFecBlocks() {
     return nb_fec_blocks;
@@ -350,6 +370,9 @@ SWGRemoteOutputSettings::isSet(){
         if(m_sample_rate_isSet){
             isObjectUpdated = true; break;
         }
+        if(m_tx_delay_isSet){
+            isObjectUpdated = true; break;
+        }
         if(m_nb_fec_blocks_isSet){
             isObjectUpdated = true; break;
         }

swagger/sdrangel/code/qt5/client/SWGRemoteOutputSettings.h

@@ -48,6 +48,9 @@ public:
     qint32 getSampleRate();
     void setSampleRate(qint32 sample_rate);
 
+    float getTxDelay();
+    void setTxDelay(float tx_delay);
+
     qint32 getNbFecBlocks();
     void setNbFecBlocks(qint32 nb_fec_blocks);
 
@@ -91,6 +94,9 @@ private:
     qint32 sample_rate;
     bool m_sample_rate_isSet;
 
+    float tx_delay;
+    bool m_tx_delay_isSet;
+
     qint32 nb_fec_blocks;
     bool m_nb_fec_blocks_isSet;
 

swagger/sdrangel/examples/rx_test.py

@@ -53,6 +53,7 @@ def getInputOptions():
     parser.add_option("--rmt-address", dest="remote_address", help="RemoteSink: destination data address", metavar="IP_ADDRESS", type="string")
     parser.add_option("--rmt-port", dest="remote_port", help="RemoteSink: destination data port", metavar="PORT", type="int")
     parser.add_option("--rmt-fec", dest="remote_fec", help="RemoteSink: number of FEC blocks per frame", metavar="NUMBER", type="int")
+    parser.add_option("--rmt-txdelay", dest="remote_tx_delay", help="RemoteSink: inter block UDP Tx delay percentage", metavar="PERCENT", type="int")
 
     (options, args) = parser.parse_args()
 
@@ -325,6 +326,8 @@ def setupChannel(deviceset_url, options):
             settings["RemoteSinkSettings"]["dataPort"] = options.remote_port
         if options.remote_fec:
             settings["RemoteSinkSettings"]["nbFECBlocks"] = options.remote_fec
+        if options.remote_tx_delay:
+            settings["RemoteSinkSettings"]["txDelay"] = options.remote_tx_delay
 
     r = callAPI(deviceset_url + "/channel/%d/settings" % i, "PATCH", None, settings, "Change demod")
     if r is None:

swagger/sdrangel/examples/test.json

@@ -63,6 +63,7 @@
               "reverseAPIPort": 8888,
               "rgbColor": -7601148,
               "title": "Channel 0",
+              "txDelay": 0,
               "useReverseAPI": 0
             },
             "channelType": "RemoteSink",
@@ -97,6 +98,7 @@
               "reverseAPIPort": 8888,
               "rgbColor": -7601148,
               "title": "Remote sink",
+              "txDelay": 0,
               "useReverseAPI": 0
             },
             "channelType": "RemoteSink",
@@ -131,6 +133,7 @@
               "reverseAPIPort": 8888,
               "rgbColor": -7601148,
               "title": "Remote sink",
+              "txDelay": 0,
               "useReverseAPI": 0
             },
             "channelType": "RemoteSink",
@@ -145,4 +148,4 @@
         null,
         "Start device on deviceset R0"
     ]
-]
+]