/////////////////////////////////////////////////////////////////////////////////// // Copyright (C) 2019 Edouard Griffiths, F4EXB. // // // // This program is free software; you can redistribute it and/or modify // // it under the terms of the GNU General Public License as published by // // the Free Software Foundation as version 3 of the License, or // // (at your option) any later version. // // // // This program is distributed in the hope that it will be useful, // // but WITHOUT ANY WARRANTY; without even the implied warranty of // // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // // GNU General Public License V3 for more details. // // // // You should have received a copy of the GNU General Public License // // along with this program. If not, see . // /////////////////////////////////////////////////////////////////////////////////// #include "freqtracker.h" #include #include #include #include #include #include #include #include #include "SWGChannelSettings.h" #include "SWGFreqTrackerSettings.h" #include "SWGChannelReport.h" #include "SWGFreqTrackerReport.h" #include "dsp/downchannelizer.h" #include "audio/audiooutput.h" #include "dsp/dspengine.h" #include "dsp/threadedbasebandsamplesink.h" #include "dsp/dspcommands.h" #include "dsp/fftfilt.h" #include "device/devicesourceapi.h" #include "util/db.h" #include "util/stepfunctions.h" MESSAGE_CLASS_DEFINITION(FreqTracker::MsgConfigureFreqTracker, Message) MESSAGE_CLASS_DEFINITION(FreqTracker::MsgSampleRateNotification, Message) MESSAGE_CLASS_DEFINITION(FreqTracker::MsgConfigureChannelizer, Message) const QString FreqTracker::m_channelIdURI = "sdrangel.channel.freqtracker"; const QString FreqTracker::m_channelId = "FreqTracker"; const int FreqTracker::m_udpBlockSize = 512; FreqTracker::FreqTracker(DeviceSourceAPI *deviceAPI) : ChannelSinkAPI(m_channelIdURI), m_deviceAPI(deviceAPI), m_deviceSampleRate(48000), m_inputSampleRate(48000), m_inputFrequencyOffset(0), m_channelSampleRate(48000), m_running(false), m_squelchOpen(false), m_squelchGate(0), m_magsqSum(0.0f), m_magsqPeak(0.0f), m_magsqCount(0), m_timerConnected(false), m_tickCount(0), m_lastCorrAbs(0), m_avgDeltaFreq(0.0), m_settingsMutex(QMutex::Recursive) { setObjectName(m_channelId); #ifdef USE_INTERNAL_TIMER #warning "Uses internal timer" m_timer = new QTimer(); m_timer->start(50); #else m_timer = &DSPEngine::instance()->getMasterTimer(); #endif m_magsq = 0.0; m_rrcFilter = new fftfilt(m_settings.m_rfBandwidth / m_channelSampleRate, 2*1024); m_pll.computeCoefficients(0.002f, 0.5f, 10.0f); // bandwidth, damping factor, loop gain applyChannelSettings(m_inputSampleRate, m_inputFrequencyOffset, true); m_channelizer = new DownChannelizer(this); m_threadedChannelizer = new ThreadedBasebandSampleSink(m_channelizer, this); m_deviceAPI->addThreadedSink(m_threadedChannelizer); m_deviceAPI->addChannelAPI(this); m_networkManager = new QNetworkAccessManager(); connect(m_networkManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(networkManagerFinished(QNetworkReply*))); } FreqTracker::~FreqTracker() { disconnectTimer(); #ifdef USE_INTERNAL_TIMER m_timer->stop(); delete m_timer; #endif disconnect(m_networkManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(networkManagerFinished(QNetworkReply*))); delete m_networkManager; m_deviceAPI->removeChannelAPI(this); m_deviceAPI->removeThreadedSink(m_threadedChannelizer); delete m_threadedChannelizer; delete m_channelizer; delete m_rrcFilter; } void FreqTracker::feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end, bool firstOfBurst) { (void) firstOfBurst; Complex ci; if (!m_running) { return; } m_settingsMutex.lock(); for (SampleVector::const_iterator it = begin; it != end; ++it) { Complex c(it->real(), it->imag()); c *= m_nco.nextIQ(); if (m_interpolatorDistance < 1.0f) // interpolate { processOneSample(ci); while (m_interpolator.interpolate(&m_interpolatorDistanceRemain, c, &ci)) { processOneSample(ci); } m_interpolatorDistanceRemain += m_interpolatorDistance; } else // decimate { if (m_interpolator.decimate(&m_interpolatorDistanceRemain, c, &ci)) { processOneSample(ci); m_interpolatorDistanceRemain += m_interpolatorDistance; } } } m_settingsMutex.unlock(); } void FreqTracker::processOneSample(Complex &ci) { fftfilt::cmplx *sideband; int n_out; if (m_settings.m_rrc) { n_out = m_rrcFilter->runFilt(ci, &sideband); } else { n_out = 1; sideband = &ci; } for (int i = 0; i < n_out; i++) { Real re = sideband[i].real() / SDR_RX_SCALEF; Real im = sideband[i].imag() / SDR_RX_SCALEF; Real magsq = re*re + im*im; m_movingAverage(magsq); m_magsq = m_movingAverage.asDouble(); m_magsqSum += magsq; if (magsq > m_magsqPeak) { m_magsqPeak = magsq; } m_magsqCount++; if (m_magsq < m_squelchLevel) { if (m_squelchGate > 0) { if (m_squelchCount > 0) { m_squelchCount--; } m_squelchOpen = m_squelchCount >= m_squelchGate; } else { m_squelchOpen = false; } } else { if (m_squelchGate > 0) { if (m_squelchCount < 2*m_squelchGate) { m_squelchCount++; } m_squelchOpen = m_squelchCount >= m_squelchGate; } else { m_squelchOpen = true; } } if (m_squelchOpen) { if (m_settings.m_trackerType == FreqTrackerSettings::TrackerFLL) { m_fll.feed(re, im); } else if (m_settings.m_trackerType == FreqTrackerSettings::TrackerPLL) { m_pll.feed(re, im); } } } } void FreqTracker::start() { qDebug("FreqTracker::start"); m_squelchCount = 0; applyChannelSettings(m_inputSampleRate, m_inputFrequencyOffset, true); m_running = true; } void FreqTracker::stop() { qDebug("FreqTracker::stop"); m_running = false; } Real FreqTracker::getFrequency() const { if (m_settings.m_trackerType == FreqTrackerSettings::TrackerPLL) { return (m_pll.getFreq() * m_channelSampleRate) / (2.0 * M_PI); } else if (m_settings.m_trackerType == FreqTrackerSettings::TrackerFLL) { return (m_fll.getFreq() * m_channelSampleRate) / (2.0 * M_PI); } else { return 0; } } bool FreqTracker::handleMessage(const Message& cmd) { if (DSPSignalNotification::match(cmd)) { DSPSignalNotification& notif = (DSPSignalNotification&) cmd; m_deviceSampleRate = notif.getSampleRate(); qDebug() << "FreqTracker::handleMessage: DSPSignalNotification:" << " m_deviceSampleRate: " << m_deviceSampleRate << " centerFrequency: " << notif.getCenterFrequency(); configureChannelizer(); return true; } else if (DownChannelizer::MsgChannelizerNotification::match(cmd)) { DownChannelizer::MsgChannelizerNotification& notif = (DownChannelizer::MsgChannelizerNotification&) cmd; if (!m_settings.m_tracking) { qDebug() << "FreqTracker::handleMessage: MsgChannelizerNotification:" << " inputSampleRate: " << notif.getSampleRate() << " inputFrequencyOffset: " << notif.getFrequencyOffset(); } applyChannelSettings(notif.getSampleRate(), notif.getFrequencyOffset()); setInterpolator(); return true; } else if (MsgConfigureFreqTracker::match(cmd)) { MsgConfigureFreqTracker& cfg = (MsgConfigureFreqTracker&) cmd; qDebug() << "FreqTracker::handleMessage: MsgConfigureFreqTracker"; applySettings(cfg.getSettings(), cfg.getForce()); return true; } else { return false; } } void FreqTracker::applyChannelSettings(int inputSampleRate, int inputFrequencyOffset, bool force) { if (!m_settings.m_tracking) { qDebug() << "FreqTracker::applyChannelSettings:" << " inputSampleRate: " << inputSampleRate << " inputFrequencyOffset: " << inputFrequencyOffset; } if ((m_inputFrequencyOffset != inputFrequencyOffset) || (m_inputSampleRate != inputSampleRate) || force) { m_nco.setFreq(-inputFrequencyOffset, inputSampleRate); } if ((m_inputSampleRate != inputSampleRate) || force) { setInterpolator(); } m_inputSampleRate = inputSampleRate; m_inputFrequencyOffset = inputFrequencyOffset; } void FreqTracker::applySettings(const FreqTrackerSettings& settings, bool force) { if (!settings.m_tracking) { qDebug() << "FreqTracker::applySettings:" << " m_inputFrequencyOffset: " << settings.m_inputFrequencyOffset << " m_rfBandwidth: " << settings.m_rfBandwidth << " m_log2Decim: " << settings.m_log2Decim << " m_squelch: " << settings.m_squelch << " m_rgbColor: " << settings.m_rgbColor << " m_title: " << settings.m_title << " m_alphaEMA: " << settings.m_alphaEMA << " m_tracking: " << settings.m_tracking << " m_trackerType: " << settings.m_trackerType << " m_pllPskOrder: " << settings.m_pllPskOrder << " m_rrc: " << settings.m_rrc << " m_rrcRolloff: " << settings.m_rrcRolloff << " m_useReverseAPI: " << settings.m_useReverseAPI << " m_reverseAPIAddress: " << settings.m_reverseAPIAddress << " m_reverseAPIPort: " << settings.m_reverseAPIPort << " m_reverseAPIDeviceIndex: " << settings.m_reverseAPIDeviceIndex << " m_reverseAPIChannelIndex: " << settings.m_reverseAPIChannelIndex << " force: " << force; } QList reverseAPIKeys; bool updateChannelizer = false; bool updateInterpolator = false; if ((m_settings.m_inputFrequencyOffset != settings.m_inputFrequencyOffset) || force) { reverseAPIKeys.append("inputFrequencyOffset"); updateChannelizer = true; } if ((m_settings.m_log2Decim != settings.m_log2Decim) || force) { reverseAPIKeys.append("log2Decim"); updateChannelizer = true; } if ((m_settings.m_rfBandwidth != settings.m_rfBandwidth) || force) { updateInterpolator = true; reverseAPIKeys.append("rfBandwidth"); } if ((m_settings.m_squelch != settings.m_squelch) || force) { m_squelchLevel = CalcDb::powerFromdB(settings.m_squelch); reverseAPIKeys.append("squelch"); } if ((m_settings.m_rgbColor != settings.m_rgbColor) || force) { reverseAPIKeys.append("rgbColor"); } if ((m_settings.m_title != settings.m_title) || force) { reverseAPIKeys.append("title"); } if ((m_settings.m_alphaEMA != settings.m_alphaEMA) || force) { reverseAPIKeys.append("alphaEMA"); } if ((m_settings.m_tracking != settings.m_tracking) || force) { reverseAPIKeys.append("tracking"); m_avgDeltaFreq = 0.0; m_lastCorrAbs = 0; if (settings.m_tracking) { m_pll.reset(); m_fll.reset(); } } if ((m_settings.m_trackerType != settings.m_trackerType) || force) { reverseAPIKeys.append("trackerType"); m_lastCorrAbs = 0; m_avgDeltaFreq = 0.0; if (settings.m_trackerType == FreqTrackerSettings::TrackerFLL) { m_fll.reset(); } else if (settings.m_trackerType == FreqTrackerSettings::TrackerPLL) { m_pll.reset(); } if (settings.m_trackerType == FreqTrackerSettings::TrackerNone) { disconnectTimer(); } else { connectTimer(); } } if ((m_settings.m_pllPskOrder != settings.m_pllPskOrder) || force) { reverseAPIKeys.append("pllPskOrder"); if (settings.m_pllPskOrder < 32) { m_pll.setPskOrder(settings.m_pllPskOrder); } } if ((m_settings.m_rrc != settings.m_rrc) || force) { reverseAPIKeys.append("rrc"); } if ((m_settings.m_rrcRolloff != settings.m_rrcRolloff) || force) { reverseAPIKeys.append("rrcRolloff"); updateInterpolator = true; } if ((m_settings.m_squelchGate != settings.m_squelchGate) || force) { reverseAPIKeys.append("squelchGate"); updateInterpolator = true; } if (settings.m_useReverseAPI) { bool fullUpdate = ((m_settings.m_useReverseAPI != settings.m_useReverseAPI) && settings.m_useReverseAPI) || (m_settings.m_reverseAPIAddress != settings.m_reverseAPIAddress) || (m_settings.m_reverseAPIPort != settings.m_reverseAPIPort) || (m_settings.m_reverseAPIDeviceIndex != settings.m_reverseAPIDeviceIndex) || (m_settings.m_reverseAPIChannelIndex != settings.m_reverseAPIChannelIndex); webapiReverseSendSettings(reverseAPIKeys, settings, fullUpdate || force); } m_settings = settings; if (updateChannelizer) { configureChannelizer(); } else if (updateInterpolator) { setInterpolator(); } } void FreqTracker::setInterpolator() { m_settingsMutex.lock(); m_interpolator.create(16, m_inputSampleRate, m_settings.m_rfBandwidth / 2.2f); m_interpolatorDistanceRemain = 0; m_interpolatorDistance = (Real) m_inputSampleRate / (Real) m_channelSampleRate; m_rrcFilter->create_rrc_filter(m_settings.m_rfBandwidth / m_channelSampleRate, m_settings.m_rrcRolloff / 100.0); m_squelchGate = (m_channelSampleRate / 100) * m_settings.m_squelchGate; // gate is given in 10s of ms at channel sample rate m_settingsMutex.unlock(); } void FreqTracker::configureChannelizer() { if (m_channelSampleRate != m_deviceSampleRate / (1<configure(m_channelizer->getInputMessageQueue(), m_channelSampleRate, m_settings.m_inputFrequencyOffset); if (m_guiMessageQueue) { MsgSampleRateNotification *msg = MsgSampleRateNotification::create( m_deviceSampleRate / (1<push(msg); } } void FreqTracker::connectTimer() { if (!m_timerConnected) { m_tickCount = 0; connect(m_timer, SIGNAL(timeout()), this, SLOT(tick())); m_timerConnected = true; } } void FreqTracker::disconnectTimer() { if (m_timerConnected) { disconnect(m_timer, SIGNAL(timeout()), this, SLOT(tick())); m_timerConnected = false; } } QByteArray FreqTracker::serialize() const { return m_settings.serialize(); } bool FreqTracker::deserialize(const QByteArray& data) { if (m_settings.deserialize(data)) { MsgConfigureFreqTracker *msg = MsgConfigureFreqTracker::create(m_settings, true); m_inputMessageQueue.push(msg); return true; } else { m_settings.resetToDefaults(); MsgConfigureFreqTracker *msg = MsgConfigureFreqTracker::create(m_settings, true); m_inputMessageQueue.push(msg); return false; } } int FreqTracker::webapiSettingsGet( SWGSDRangel::SWGChannelSettings& response, QString& errorMessage) { (void) errorMessage; response.setFreqTrackerSettings(new SWGSDRangel::SWGFreqTrackerSettings()); response.getFreqTrackerSettings()->init(); webapiFormatChannelSettings(response, m_settings); return 200; } int FreqTracker::webapiSettingsPutPatch( bool force, const QStringList& channelSettingsKeys, SWGSDRangel::SWGChannelSettings& response, QString& errorMessage) { (void) errorMessage; FreqTrackerSettings settings = m_settings; if (channelSettingsKeys.contains("inputFrequencyOffset")) { settings.m_inputFrequencyOffset = response.getFreqTrackerSettings()->getInputFrequencyOffset(); } if (channelSettingsKeys.contains("rfBandwidth")) { settings.m_rfBandwidth = response.getFreqTrackerSettings()->getRfBandwidth(); } if (channelSettingsKeys.contains("log2Decim")) { settings.m_log2Decim = response.getFreqTrackerSettings()->getLog2Decim(); } if (channelSettingsKeys.contains("squelch")) { settings.m_squelch = response.getFreqTrackerSettings()->getSquelch(); } if (channelSettingsKeys.contains("rgbColor")) { settings.m_rgbColor = response.getFreqTrackerSettings()->getRgbColor(); } if (channelSettingsKeys.contains("title")) { settings.m_title = *response.getFreqTrackerSettings()->getTitle(); } if (channelSettingsKeys.contains("alphaEMA")) { float alphaEMA = response.getFreqTrackerSettings()->getAlphaEma(); settings.m_alphaEMA = alphaEMA < 0.01 ? 0.01 : alphaEMA > 1.0 ? 1.0 : alphaEMA; } if (channelSettingsKeys.contains("tracking")) { settings.m_tracking = response.getFreqTrackerSettings()->getTracking() ? 1 : 0; } if (channelSettingsKeys.contains("trackerType")) { int32_t trackerTypeCode = response.getFreqTrackerSettings()->getTrackerType(); settings.m_trackerType = trackerTypeCode < 0 ? FreqTrackerSettings::TrackerFLL : trackerTypeCode > 1 ? FreqTrackerSettings::TrackerPLL : (FreqTrackerSettings::TrackerType) trackerTypeCode; } if (channelSettingsKeys.contains("pllPskOrder")) { settings.m_pllPskOrder = response.getFreqTrackerSettings()->getPllPskOrder(); } if (channelSettingsKeys.contains("rrc")) { settings.m_rrc = response.getFreqTrackerSettings()->getRrc() ? 1 : 0; } if (channelSettingsKeys.contains("rrcRolloff")) { settings.m_rrcRolloff = response.getFreqTrackerSettings()->getRrcRolloff(); } if (channelSettingsKeys.contains("useReverseAPI")) { settings.m_useReverseAPI = response.getAmDemodSettings()->getUseReverseApi() != 0; } if (channelSettingsKeys.contains("reverseAPIAddress")) { settings.m_reverseAPIAddress = *response.getAmDemodSettings()->getReverseApiAddress(); } if (channelSettingsKeys.contains("reverseAPIPort")) { settings.m_reverseAPIPort = response.getAmDemodSettings()->getReverseApiPort(); } if (channelSettingsKeys.contains("reverseAPIDeviceIndex")) { settings.m_reverseAPIDeviceIndex = response.getAmDemodSettings()->getReverseApiDeviceIndex(); } if (channelSettingsKeys.contains("reverseAPIChannelIndex")) { settings.m_reverseAPIChannelIndex = response.getAmDemodSettings()->getReverseApiChannelIndex(); } MsgConfigureFreqTracker *msg = MsgConfigureFreqTracker::create(settings, force); m_inputMessageQueue.push(msg); qDebug("FreqTracker::webapiSettingsPutPatch: forward to GUI: %p", m_guiMessageQueue); if (m_guiMessageQueue) // forward to GUI if any { MsgConfigureFreqTracker *msgToGUI = MsgConfigureFreqTracker::create(settings, force); m_guiMessageQueue->push(msgToGUI); } webapiFormatChannelSettings(response, settings); return 200; } int FreqTracker::webapiReportGet( SWGSDRangel::SWGChannelReport& response, QString& errorMessage) { (void) errorMessage; response.setFreqTrackerReport(new SWGSDRangel::SWGFreqTrackerReport()); response.getFreqTrackerReport()->init(); webapiFormatChannelReport(response); return 200; } void FreqTracker::webapiFormatChannelSettings(SWGSDRangel::SWGChannelSettings& response, const FreqTrackerSettings& settings) { response.getFreqTrackerSettings()->setInputFrequencyOffset(settings.m_inputFrequencyOffset); response.getFreqTrackerSettings()->setRfBandwidth(settings.m_rfBandwidth); response.getFreqTrackerSettings()->setRgbColor(settings.m_rgbColor); response.getFreqTrackerSettings()->setSquelch(settings.m_squelch); if (response.getFreqTrackerSettings()->getTitle()) { *response.getFreqTrackerSettings()->getTitle() = settings.m_title; } else { response.getFreqTrackerSettings()->setTitle(new QString(settings.m_title)); } response.getFreqTrackerSettings()->setTrackerType((int) m_settings.m_trackerType); response.getFreqTrackerSettings()->setUseReverseApi(settings.m_useReverseAPI ? 1 : 0); if (response.getFreqTrackerSettings()->getReverseApiAddress()) { *response.getFreqTrackerSettings()->getReverseApiAddress() = settings.m_reverseAPIAddress; } else { response.getFreqTrackerSettings()->setReverseApiAddress(new QString(settings.m_reverseAPIAddress)); } response.getFreqTrackerSettings()->setReverseApiPort(settings.m_reverseAPIPort); response.getFreqTrackerSettings()->setReverseApiDeviceIndex(settings.m_reverseAPIDeviceIndex); response.getFreqTrackerSettings()->setReverseApiChannelIndex(settings.m_reverseAPIChannelIndex); } void FreqTracker::webapiFormatChannelReport(SWGSDRangel::SWGChannelReport& response) { double magsqAvg, magsqPeak; int nbMagsqSamples; getMagSqLevels(magsqAvg, magsqPeak, nbMagsqSamples); response.getFreqTrackerReport()->setChannelPowerDb(CalcDb::dbPower(magsqAvg)); response.getFreqTrackerReport()->setSquelch(m_squelchOpen ? 1 : 0); response.getFreqTrackerReport()->setSampleRate(m_channelSampleRate); response.getFreqTrackerReport()->setChannelSampleRate(m_inputSampleRate); } void FreqTracker::webapiReverseSendSettings(QList& channelSettingsKeys, const FreqTrackerSettings& settings, bool force) { SWGSDRangel::SWGChannelSettings *swgChannelSettings = new SWGSDRangel::SWGChannelSettings(); swgChannelSettings->setTx(0); swgChannelSettings->setOriginatorChannelIndex(getIndexInDeviceSet()); swgChannelSettings->setOriginatorDeviceSetIndex(getDeviceSetIndex()); swgChannelSettings->setChannelType(new QString("FreqTracker")); swgChannelSettings->setFreqTrackerSettings(new SWGSDRangel::SWGFreqTrackerSettings()); SWGSDRangel::SWGFreqTrackerSettings *swgFreqTrackerSettings = swgChannelSettings->getFreqTrackerSettings(); // transfer data that has been modified. When force is on transfer all data except reverse API data if (channelSettingsKeys.contains("inputFrequencyOffset") || force) { swgFreqTrackerSettings->setInputFrequencyOffset(settings.m_inputFrequencyOffset); } if (channelSettingsKeys.contains("rfBandwidth") || force) { swgFreqTrackerSettings->setRfBandwidth(settings.m_rfBandwidth); } if (channelSettingsKeys.contains("rgbColor") || force) { swgFreqTrackerSettings->setRgbColor(settings.m_rgbColor); } if (channelSettingsKeys.contains("squelch") || force) { swgFreqTrackerSettings->setSquelch(settings.m_squelch); } if (channelSettingsKeys.contains("title") || force) { swgFreqTrackerSettings->setTitle(new QString(settings.m_title)); } if (channelSettingsKeys.contains("trackerType") || force) { swgFreqTrackerSettings->setTrackerType((int) settings.m_trackerType); } QString channelSettingsURL = QString("http://%1:%2/sdrangel/deviceset/%3/channel/%4/settings") .arg(settings.m_reverseAPIAddress) .arg(settings.m_reverseAPIPort) .arg(settings.m_reverseAPIDeviceIndex) .arg(settings.m_reverseAPIChannelIndex); m_networkRequest.setUrl(QUrl(channelSettingsURL)); m_networkRequest.setHeader(QNetworkRequest::ContentTypeHeader, "application/json"); QBuffer *buffer=new QBuffer(); buffer->open((QBuffer::ReadWrite)); buffer->write(swgChannelSettings->asJson().toUtf8()); buffer->seek(0); // Always use PATCH to avoid passing reverse API settings m_networkManager->sendCustomRequest(m_networkRequest, "PATCH", buffer); delete swgChannelSettings; } void FreqTracker::networkManagerFinished(QNetworkReply *reply) { QNetworkReply::NetworkError replyError = reply->error(); if (replyError) { qWarning() << "FreqTracker::networkManagerFinished:" << " error(" << (int) replyError << "): " << replyError << ": " << reply->errorString(); return; } QString answer = reply->readAll(); answer.chop(1); // remove last \n qDebug("FreqTracker::networkManagerFinished: reply:\n%s", answer.toStdString().c_str()); } void FreqTracker::tick() { if (getSquelchOpen()) { m_avgDeltaFreq = m_settings.m_alphaEMA*getFrequency() + (1.0 - m_settings.m_alphaEMA)*m_avgDeltaFreq; } if (m_tickCount < 19) { m_tickCount++; } else { if ((m_settings.m_tracking) && getSquelchOpen()) { uint32_t decayDivider = 1000.0 * m_settings.m_alphaEMA; int decayAmount = m_channelSampleRate < decayDivider ? 1 : m_channelSampleRate / decayDivider; int trim = m_channelSampleRate / 1000; if (m_lastCorrAbs < decayAmount) { m_lastCorrAbs = m_avgDeltaFreq < 0 ? -m_avgDeltaFreq : m_avgDeltaFreq; if (m_lastCorrAbs > trim) { FreqTrackerSettings settings = m_settings; settings.m_inputFrequencyOffset += m_avgDeltaFreq; applySettings(settings); } } else { m_lastCorrAbs -= decayAmount; } } m_tickCount = 0; } }