partial eye diagram implementation

Software/PC_Application/LibreVNA-GUI/LibreVNA-GUI.pro

@@ -33,6 +33,7 @@ HEADERS += \
     SpectrumAnalyzer/spectrumanalyzer.h \
     SpectrumAnalyzer/tracewidgetsa.h \
     Tools/eseries.h \
+    Tools/eyediagramdialog.h \
     Tools/impedancematchdialog.h \
     Tools/parameters.h \
     Traces/Marker/marker.h \
@@ -112,6 +113,7 @@ HEADERS += \
     Traces/waterfallaxisdialog.h \
     Traces/xyplotaxisdialog.h \
     Traces/tracepolarchart.h \
+    Util/prbs.h \
     Util/qpointervariant.h \
     Util/util.h \
     Util/app_common.h \
@@ -175,6 +177,7 @@ SOURCES += \
     SpectrumAnalyzer/spectrumanalyzer.cpp \
     SpectrumAnalyzer/tracewidgetsa.cpp \
     Tools/eseries.cpp \
+    Tools/eyediagramdialog.cpp \
     Tools/impedancematchdialog.cpp \
     Tools/parameters.cpp \
     Traces/Marker/marker.cpp \
@@ -243,6 +246,7 @@ SOURCES += \
     Traces/tracepolar.cpp \
     Traces/waterfallaxisdialog.cpp \
     Traces/xyplotaxisdialog.cpp \
+    Util/prbs.cpp \
     Util/util.cpp \
     VNA/Deembedding/deembedding.cpp \
     VNA/Deembedding/deembeddingdialog.cpp \
@@ -301,6 +305,7 @@ FORMS += \
     Device/firmwareupdatedialog.ui \
     Device/manualcontroldialog.ui \
     Generator/signalgenwidget.ui \
+    Tools/eyediagramdialog.ui \
     Tools/impedancematchdialog.ui \
     Traces/Marker/markerwidget.ui \
     Traces/Math/dftdialog.ui \
@@ -343,7 +348,7 @@ RESOURCES += \
     icons.qrc \
     resources/librevna.qrc
 
-QMAKE_CXXFLAGS += -Wno-deprecated -Wno-deprecated-declarations
+QMAKE_CXXFLAGS += -Wno-deprecated -Wno-deprecated-declarations -Wno-deprecated-copy
 
 CONFIG += c++17
 REVISION = $$system(git rev-parse HEAD)

Software/PC_Application/LibreVNA-GUI/Tools/eyediagramdialog.cpp

@@ -0,0 +1,412 @@
+#include "eyediagramdialog.h"
+#include "ui_eyediagramdialog.h"
+#include "Util/prbs.h"
+#include "Traces/Math/tdr.h"
+#include "Util/util.h"
+#include "preferences.h"
+#include "Traces/fftcomplex.h"
+
+#include <random>
+#include <thread>
+#include <chrono>
+
+#include <QPainter>
+
+using namespace std::chrono_literals;
+
+EyeDiagramDialog::EyeDiagramDialog(TraceModel &model) :
+    QDialog(nullptr),
+    ui(new Ui::EyeDiagramDialog)
+{
+    ui->setupUi(this);
+
+    workingBuffer = &eyeBuffer[0];
+    finishedBuffer = &eyeBuffer[1];
+
+    updating = false;
+
+    trace = nullptr;
+    ui->update->setEnabled(false);
+
+    ui->datarate->setUnit("bps");
+    ui->datarate->setPrefixes(" kMG");
+    ui->datarate->setPrecision(3);
+
+    ui->risetime->setUnit("s");
+    ui->risetime->setPrefixes("pnum ");
+    ui->risetime->setPrecision(3);
+
+    ui->falltime->setUnit("s");
+    ui->falltime->setPrefixes("pnum ");
+    ui->falltime->setPrecision(3);
+
+    ui->highLevel->setUnit("V");
+    ui->highLevel->setPrefixes("m ");
+    ui->highLevel->setPrecision(3);
+
+    ui->lowLevel->setUnit("V");
+    ui->lowLevel->setPrefixes("m ");
+    ui->lowLevel->setPrecision(3);
+
+    ui->noise->setUnit("V");
+    ui->noise->setPrefixes("um ");
+    ui->noise->setPrecision(3);
+
+    ui->jitter->setUnit("s");
+    ui->jitter->setPrefixes("pnum ");
+    ui->jitter->setPrecision(3);
+
+    ui->datarate->setValue(100000000);
+    ui->risetime->setValue(0.000000001);
+    ui->falltime->setValue(0.000000001);
+    ui->highLevel->setValue(1);
+    ui->lowLevel->setValue(0);
+    ui->noise->setValue(0.01);
+    ui->jitter->setValue(0.0000000001);
+
+    ui->displayedCycles->setValue(200);
+
+    ui->widget->setDialog(this);
+
+    connect(this, &EyeDiagramDialog::updatePercent, ui->progress, &QProgressBar::setValue, Qt::QueuedConnection);
+    connect(ui->update, &QPushButton::clicked, this, &EyeDiagramDialog::triggerUpdate);
+    connect(this, &EyeDiagramDialog::updateDone, ui->widget, qOverload<>(&QWidget::update));
+
+    connect(ui->traceSelector, qOverload<int>(&QComboBox::currentIndexChanged), [=](){
+        trace = qvariant_cast<Trace*>(ui->traceSelector->itemData(ui->traceSelector->currentIndex()));
+        ui->update->setEnabled(true);
+    });
+
+    // find applicable traces
+    for(auto t : model.getTraces()) {
+        if(t->getDataType() != Trace::DataType::Frequency) {
+            // wrong domain
+            continue;
+        }
+        if(t->isReflection()) {
+            // can't work with reflection measurements
+            continue;
+        }
+        if(t->numSamples() < 100) {
+            // not enough samples
+            continue;
+        }
+        auto start = t->getSample(0).x;
+        auto stop = t->getSample(t->numSamples() - 1).x;
+        if(stop - start < start * 100) {
+            // span/start is not suitable for step response TDR
+            continue;
+        }
+        // can use this trace
+        ui->traceSelector->addItem(t->name(), QVariant::fromValue<Trace*>(t));
+    }
+}
+
+EyeDiagramDialog::~EyeDiagramDialog()
+{
+    delete ui;
+}
+
+double EyeDiagramDialog::getIntensity(unsigned int x, unsigned int y)
+{
+    if(finishedBuffer->size() > x) {
+        if((*finishedBuffer)[x].size() > y) {
+            return (*finishedBuffer)[x][y];
+        }
+    }
+    return std::numeric_limits<double>::quiet_NaN();
+}
+
+bool EyeDiagramDialog::triggerUpdate()
+{
+    update(ui->widget->width(), ui->widget->height());
+}
+
+bool EyeDiagramDialog::update(unsigned int width, unsigned int height)
+{
+    if(updating) {
+        // already updating, can't start again
+        return false;
+    }
+    updating = true;
+    new std::thread(&EyeDiagramDialog::updateThread, this, width, height);
+}
+
+void EyeDiagramDialog::updateThread(unsigned int width, unsigned int height)
+{
+    emit updatePercent(0);
+    if(!trace) {
+        updating = false;
+        return;
+    }
+
+    qDebug() << "Starting eye diagram calculation";
+
+    auto datarate = ui->datarate->value();
+    auto highlevel = ui->highLevel->value();
+    auto lowlevel = ui->lowLevel->value();
+    auto risetime = ui->risetime->value();
+    auto falltime = ui->falltime->value();
+    auto noise = ui->noise->value();
+    auto jitter = ui->jitter->value();
+    unsigned int patternbits = ui->patternLength->currentIndex() + 2;
+    unsigned int cycles = ui->displayedCycles->value() + 1; // first cycle will not be displayed
+
+    // sanity check values
+    // TODO
+
+    qDebug() << "Eye calculation: input values okay";
+
+    // resize working buffer
+    workingBuffer->clear();
+    workingBuffer->resize(width);
+    for(auto& y : *workingBuffer) {
+        y.resize(height, 0.0);
+    }
+
+    // calculate timestep
+    double displayedTime = 2 * 1.0/datarate; // always showing two bit periods
+    double timestep = displayedTime / (width);
+
+    auto prbs = new PRBS(patternbits);
+
+    bool currentBit = prbs->next();
+    bool nextBit = prbs->next();
+
+    // initialize random generator
+    std::random_device rd1;
+    std::mt19937 mt_noise(rd1());
+    std::normal_distribution<> dist_noise(0, noise);
+
+    std::random_device rd2;
+    std::mt19937 mt_jitter(rd2());
+    std::normal_distribution<> dist_jitter(0, jitter);
+
+    // reserve vector for input data
+    std::vector<double> input(width * cycles, 0.0);
+
+    unsigned int bitcnt = 1;
+    double transitionTime = -10; // assume that we start with a settled input, last transition was "long" ago
+    for(unsigned int i=0;i<input.size();i++) {
+        double time = i*timestep;
+        double voltage;
+        if(time >= transitionTime) {
+            // currently within a bit transition
+            double edgeTime = 0;
+            if(!currentBit && nextBit) {
+                edgeTime = risetime;
+            } else if(currentBit && !nextBit) {
+                edgeTime = falltime;
+            }
+            if(time >= transitionTime + edgeTime) {
+                // bit transition settled
+                voltage = nextBit ? highlevel : lowlevel;
+                // move on to the next bit
+                currentBit = nextBit;
+                nextBit = prbs->next();
+                transitionTime = bitcnt * 1.0 / datarate + dist_jitter(mt_jitter);
+                bitcnt++;
+            } else {
+                // still within rise or fall time
+                double timeSinceEdge = time - transitionTime;
+                double edgeRatio = timeSinceEdge / edgeTime;
+                double from = currentBit ? highlevel : lowlevel;
+                double to = nextBit ? highlevel : lowlevel;
+                voltage = from * (1.0 - edgeRatio) + to * edgeRatio;
+            }
+        } else {
+            // still before the next edge
+            voltage = currentBit ? highlevel : lowlevel;
+        }
+        voltage += dist_noise(mt_noise);
+        input[i] = voltage;
+    }
+
+    // input voltage vector fully assembled
+    qDebug() << "Eye calculation: input data generated";
+
+    // calculate impulse response of trace
+    auto tdr = new Math::TDR();
+    // default configuration of TDR is lowpass with automatic DC, which is exactly what we need
+
+    // TDR calculation happens in background thread, need to wait for emitted signal
+    volatile bool TDRdone = false;
+
+    double eyeTimeShift = 0;
+
+    std::vector<double> convolutionData;
+    auto conn = connect(tdr, &Math::TDR::outputSamplesChanged, [&](){
+        if(!TDRdone) {
+            // determine how long the impulse response is
+            auto samples = tdr->numSamples();
+            auto length = tdr->getSample(samples - 1).x;
+
+            // determine average delay
+            auto total_step = tdr->getStepResponse(samples - 1);
+            for(unsigned int i=0;i<samples;i++) {
+                auto step = tdr->getStepResponse(i);
+                if(abs(total_step - step) <= abs(step)) {
+                    // mid point reached
+                    eyeTimeShift = tdr->getSample(i).x;
+                    break;
+                }
+            }
+
+            auto scale = timestep / (length / (samples - 1));
+            unsigned long convolutedSize = length / timestep;
+            if(convolutedSize > input.size()) {
+                // impulse response is longer than what we display, truncate
+                convolutedSize = input.size();
+            }
+            convolutionData.resize(convolutedSize);
+            for(unsigned long i=0;i<convolutedSize;i++) {
+                auto x = i*timestep;
+                convolutionData[i] = tdr->getInterpolatedSample(x).y.real() * scale;
+            }
+            TDRdone = true;
+        }
+    });
+    // assigning the trace starts the TDR calculation
+    tdr->assignInput(trace);
+
+    // wait for the TDR calculation to be done
+    while(!TDRdone) {
+        std::this_thread::sleep_for(20ms);
+    };
+    disconnect(conn);
+    delete tdr;
+
+    eyeTimeShift += (risetime + falltime) / 4;
+    eyeTimeShift += 0.5 / datarate;
+    int eyeXshift = eyeTimeShift / timestep;
+
+    qDebug() << "Eye calculation: TDR calculation done";
+
+    // calculate voltage at top and bottom of diagram for y binning to pixels
+    auto eyeRange = highlevel - lowlevel;
+    auto topValue = highlevel + eyeRange * yOverrange;
+    auto bottomValue = lowlevel - eyeRange * yOverrange;
+
+    unsigned int highestIntensity = 0;
+
+    qDebug() << "Convolve via FFT start";
+    std::vector<std::complex<double>> inVec;
+    std::vector<std::complex<double>> impulseVec;
+    std::vector<std::complex<double>> outVec;
+    for(auto i : input) {
+        inVec.push_back(i);
+    }
+    for(auto i : convolutionData) {
+        impulseVec.push_back(i);
+    }
+    impulseVec.resize(inVec.size(), 0.0);
+    outVec.resize(inVec.size());
+    Fft::convolve(inVec, impulseVec, outVec);
+    qDebug() << "Convolve via FFT stop";
+
+    auto addLine = [&](int x0, int y0, int x1, int y1, bool skipFirst = true) {
+        bool first = true;
+        auto putpixel = [&](int x, int y) {
+            if(skipFirst && first) {
+                first = false;
+                return;
+            }
+            if(x < 0 || x >= width || y < 0 || y >= height) {
+                return;
+            }
+            auto &bin = (*workingBuffer)[x][y];
+            bin++;
+            if(bin > highestIntensity) {
+                highestIntensity = bin;
+            }
+        };
+
+        int dx =  abs (x1 - x0), sx = x0 < x1 ? 1 : -1;
+        int dy = -abs (y1 - y0), sy = y0 < y1 ? 1 : -1;
+        int err = dx + dy, e2; /* error value e_xy */
+
+        for (;;){  /* loop */
+            putpixel (x0,y0);
+            if (x0 == x1 && y0 == y1) break;
+            e2 = 2 * err;
+            if (e2 >= dy) { err += dy; x0 += sx; } /* e_xy+e_x > 0 */
+            if (e2 <= dx) { err += dx; y0 += sy; } /* e_xy+e_y < 0 */
+        }
+    };
+
+    // got the input data and the convolution data, calculate output
+    int lastyBin;
+    for(unsigned int i=width;i<input.size();i++) {
+//        double voltage = 0;
+//        for(unsigned j=0;j<convolutionData.size();j++) {
+//            double inputValue = i >= j ? input[i-j] : input[0];
+//            voltage += convolutionData[j] * inputValue;
+//        }
+        double voltage = outVec[i].real();
+        int yBin = Util::Scale<double>(voltage, bottomValue, topValue, height-1, 0);
+        // increment pixel bin
+        if(yBin < 0) {
+            yBin = 0;
+        } else if(yBin >= height) {
+            yBin = height - 1;
+        }
+
+        auto xlast = (i-1-eyeXshift)%width;
+        auto xnow = (i-eyeXshift)%width;
+        if(xnow > xlast && i > width) {
+            addLine(xlast, lastyBin, xnow, yBin, xlast > 0);
+        }
+        lastyBin = yBin;
+        emit updatePercent(100 * i / input.size());
+    }
+
+    qDebug() << "Eye calculation: Convolution done";
+
+    // normalize intensity
+    for(auto &y : *workingBuffer) {
+        for(auto &v : y) {
+            v /= highestIntensity;
+        }
+    }
+    emit updatePercent(100);
+    // switch buffers
+    auto buf = finishedBuffer;
+    finishedBuffer = workingBuffer;
+    workingBuffer = buf;
+    updating = false;
+    emit updateDone();
+}
+
+EyeDiagramPlot::EyeDiagramPlot(QDialog *dialog)
+{
+    Q_UNUSED(dialog)
+}
+
+void EyeDiagramPlot::setDialog(EyeDiagramDialog *dialog)
+{
+    this->dialog = dialog;
+}
+
+void EyeDiagramPlot::paintEvent(QPaintEvent *event)
+{
+    auto &pref = Preferences::getInstance();
+    QPainter p(this);
+    p.setBackground(QBrush(pref.Graphs.Color.background));
+    p.fillRect(0, 0, width(), height(), QBrush(pref.Graphs.Color.background));
+    if(!dialog) {
+        return;
+    }
+    for(unsigned int i=0;i<width();i++) {
+        for(unsigned int j=0;j<height();j++) {
+            auto value = dialog->getIntensity(i, j);
+            if(isnan(value) || value == 0) {
+                // do not paint, just leave the background shining through
+                continue;
+            }
+            auto pen = QPen(Util::getIntensityGradeColor(value));
+            pen.setCosmetic(true);
+            p.setPen(pen);
+            p.drawPoint(i, j);
+        }
+    }
+}

Software/PC_Application/LibreVNA-GUI/Tools/eyediagramdialog.h

@@ -0,0 +1,66 @@
+#ifndef EYEDIAGRAMDIALOG_H
+#define EYEDIAGRAMDIALOG_H
+
+#include "Traces/tracemodel.h"
+
+#include <vector>
+
+#include <QDialog>
+
+namespace Ui {
+class EyeDiagramDialog;
+}
+
+class EyeDiagramDialog;
+
+class EyeDiagramPlot : public QWidget
+{
+    Q_OBJECT
+public:
+    EyeDiagramPlot(QDialog *dialog);
+
+    void setDialog(EyeDiagramDialog *dialog);
+
+private:
+    void paintEvent(QPaintEvent *event) override;
+
+    EyeDiagramDialog *dialog;
+};
+
+class EyeDiagramDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit EyeDiagramDialog(TraceModel &model);
+    ~EyeDiagramDialog();
+
+    double getIntensity(unsigned int x, unsigned int y);
+
+public slots:
+    bool triggerUpdate();
+    bool update(unsigned int width, unsigned int height);
+
+signals:
+    void updateDone();
+
+private:
+signals:
+    void updatePercent(int percent);
+
+private:
+    static constexpr double yOverrange = 0.2;
+    void updateThread(unsigned int width, unsigned int height);
+
+    Ui::EyeDiagramDialog *ui;
+
+    Trace *trace;
+
+    std::vector<std::vector<double>> eyeBuffer[2];
+    std::vector<std::vector<double>> *workingBuffer;
+    std::vector<std::vector<double>> *finishedBuffer;
+
+    bool updating;
+};
+
+#endif // EYEDIAGRAMDIALOG_H

Software/PC_Application/LibreVNA-GUI/Tools/eyediagramdialog.ui

@@ -0,0 +1,264 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>EyeDiagramDialog</class>
+ <widget class="QDialog" name="EyeDiagramDialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>909</width>
+    <height>544</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Eye Diagram</string>
+  </property>
+  <property name="modal">
+   <bool>true</bool>
+  </property>
+  <layout class="QHBoxLayout" name="horizontalLayout" stretch="0,1">
+   <item>
+    <layout class="QVBoxLayout" name="verticalLayout_2">
+     <item>
+      <widget class="QGroupBox" name="groupBox_3">
+       <property name="title">
+        <string>Trace Selection</string>
+       </property>
+       <layout class="QFormLayout" name="formLayout_3">
+        <item row="0" column="0">
+         <widget class="QLabel" name="label_11">
+          <property name="text">
+           <string>Transmission line trace:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="0" column="1">
+         <widget class="QComboBox" name="traceSelector"/>
+        </item>
+       </layout>
+      </widget>
+     </item>
+     <item>
+      <widget class="QGroupBox" name="groupBox">
+       <property name="title">
+        <string>Input Datastream Configuration</string>
+       </property>
+       <layout class="QFormLayout" name="formLayout">
+        <item row="0" column="0">
+         <widget class="QLabel" name="label">
+          <property name="text">
+           <string>Data rate:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="0" column="1">
+         <widget class="SIUnitEdit" name="datarate"/>
+        </item>
+        <item row="1" column="0">
+         <widget class="QLabel" name="label_2">
+          <property name="text">
+           <string>Rise time:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="1" column="1">
+         <widget class="SIUnitEdit" name="risetime"/>
+        </item>
+        <item row="2" column="0">
+         <widget class="QLabel" name="label_3">
+          <property name="text">
+           <string>Fall time:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="2" column="1">
+         <widget class="SIUnitEdit" name="falltime"/>
+        </item>
+        <item row="3" column="0">
+         <widget class="QLabel" name="label_4">
+          <property name="text">
+           <string>High level:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="3" column="1">
+         <widget class="SIUnitEdit" name="highLevel"/>
+        </item>
+        <item row="4" column="0">
+         <widget class="QLabel" name="label_5">
+          <property name="text">
+           <string>Low level:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="4" column="1">
+         <widget class="SIUnitEdit" name="lowLevel"/>
+        </item>
+        <item row="5" column="0">
+         <widget class="QLabel" name="label_6">
+          <property name="text">
+           <string>Noise (RMS):</string>
+          </property>
+         </widget>
+        </item>
+        <item row="5" column="1">
+         <widget class="SIUnitEdit" name="noise"/>
+        </item>
+        <item row="6" column="0">
+         <widget class="QLabel" name="label_7">
+          <property name="text">
+           <string>Jitter (RMS):</string>
+          </property>
+         </widget>
+        </item>
+        <item row="6" column="1">
+         <widget class="SIUnitEdit" name="jitter"/>
+        </item>
+        <item row="7" column="0">
+         <widget class="QLabel" name="label_8">
+          <property name="text">
+           <string>Pattern length:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="7" column="1">
+         <widget class="QComboBox" name="patternLength">
+          <property name="currentIndex">
+           <number>7</number>
+          </property>
+          <item>
+           <property name="text">
+            <string>3</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>7</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>15</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>31</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>63</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>127</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>255</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>511</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>1023</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>2047</string>
+           </property>
+          </item>
+         </widget>
+        </item>
+       </layout>
+      </widget>
+     </item>
+     <item>
+      <widget class="QGroupBox" name="groupBox_2">
+       <property name="title">
+        <string>Eye Calculation</string>
+       </property>
+       <layout class="QVBoxLayout" name="verticalLayout">
+        <item>
+         <layout class="QFormLayout" name="formLayout_2">
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_9">
+            <property name="text">
+             <string>Displayed cycles:</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QSpinBox" name="displayedCycles">
+            <property name="minimum">
+             <number>1</number>
+            </property>
+            <property name="maximum">
+             <number>1000</number>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_10">
+            <property name="text">
+             <string>Update when trace changes:</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="1">
+           <widget class="QCheckBox" name="updateOnTraceChange">
+            <property name="text">
+             <string/>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </item>
+        <item>
+         <widget class="QPushButton" name="update">
+          <property name="text">
+           <string>Update</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QProgressBar" name="progress">
+          <property name="value">
+           <number>0</number>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <widget class="EyeDiagramPlot" name="widget" native="true"/>
+   </item>
+  </layout>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>SIUnitEdit</class>
+   <extends>QLineEdit</extends>
+   <header>CustomWidgets/siunitedit.h</header>
+  </customwidget>
+  <customwidget>
+   <class>EyeDiagramPlot</class>
+   <extends>QWidget</extends>
+   <header>Tools/eyediagramdialog.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
+ <resources/>
+ <connections/>
+</ui>

Software/PC_Application/LibreVNA-GUI/Tools/impedancematchdialog.ui

@@ -450,8 +450,8 @@
   </connection>
  </connections>
  <buttongroups>
+  <buttongroup name="lGroup"/>
   <buttongroup name="zGroup"/>
   <buttongroup name="cGroup"/>
-  <buttongroup name="lGroup"/>
  </buttongroups>
 </ui>

Software/PC_Application/LibreVNA-GUI/Traces/Math/tdr.h

@@ -16,7 +16,7 @@ class TDRThread : public QThread
     Q_OBJECT
 public:
     TDRThread(TDR &tdr);
-    ~TDRThread(){};
+    ~TDRThread(){}
 private:
     void run() override;
     TDR &tdr;
@@ -38,7 +38,7 @@ public:
 
     virtual nlohmann::json toJSON() override;
     virtual void fromJSON(nlohmann::json j) override;
-    Type getType() override {return Type::TDR;};
+    Type getType() override {return Type::TDR;}
 
     enum class Mode {
         Lowpass,

Software/PC_Application/LibreVNA-GUI/Traces/Math/tracemath.h

@@ -101,13 +101,13 @@ public:
     // indicate whether this function produces time or frequency domain data
     virtual DataType outputType(DataType inputType) = 0;
     virtual QString description() = 0;
-    virtual void edit(){};
+    virtual void edit(){}
 
     void removeInput();
     void assignInput(TraceMath *input);
 
     DataType getDataType() const;
-    std::vector<Data>& rData() { return data;};
+    std::vector<Data>& rData() { return data;}
     Status getStatus() const;
     QString getStatusDescription() const;
     virtual Type getType() = 0;
@@ -119,7 +119,7 @@ public:
 
 public slots:
     // some values of the input data have changed, begin/end determine which sample(s) has changed
-    virtual void inputSamplesChanged(unsigned int begin, unsigned int end){Q_UNUSED(begin) Q_UNUSED(end)};
+    virtual void inputSamplesChanged(unsigned int begin, unsigned int end){Q_UNUSED(begin) Q_UNUSED(end)}
 
     void inputTypeChanged(DataType type);
 

Software/PC_Application/LibreVNA-GUI/Traces/tracewaterfall.cpp

@@ -241,7 +241,7 @@ void TraceWaterfall::draw(QPainter &p)
     }
     p.drawRect(legendRect);
     for(int i=plotAreaTop + 1;i<plotAreaBottom;i++) {
-        auto color = getColor(Util::Scale<double>(i, plotAreaTop, plotAreaBottom, 1.0, 0.0));
+        auto color = Util::getIntensityGradeColor(Util::Scale<double>(i, plotAreaTop, plotAreaBottom, 1.0, 0.0));
         p.setPen(QColor(color));
         pen.setCosmetic(true);
         p.drawLine(legendRect.x()+1, i, legendRect.x()+legendRect.width()-1, i);
@@ -387,7 +387,7 @@ void TraceWaterfall::draw(QPainter &p)
                 }
                 x_stop = xAxis.transform(x_stop, plotAreaLeft, plotAreaLeft + plotAreaWidth);
                 auto y = yAxis.sampleToCoordinate(sweep[s]);
-                auto color = getColor(yAxis.transform(y, 0.0, 1.0));
+                auto color = Util::getIntensityGradeColor(yAxis.transform(y, 0.0, 1.0));
                 auto rect = QRect(round(x_start), ytop, round(x_stop - x_start) + 1, ybottom - ytop + 1);
                 p.fillRect(rect, QBrush(color));
             }
@@ -569,19 +569,6 @@ void TraceWaterfall::updateYAxis()
     }
 }
 
-QColor TraceWaterfall::getColor(double scale)
-{
-    if(scale < 0.0) {
-        return Qt::black;
-    } else if(scale > 1.0) {
-        return Qt::white;
-    } else if(scale >= 0.0 && scale <= 1.0) {
-        return QColor::fromHsv(Util::Scale<double>(scale, 0.0, 1.0, 240, 0), 255, 255);
-    } else {
-        return Qt::black;
-    }
-}
-
 QString TraceWaterfall::AlignmentToString(Alignment a)
 {
     switch(a) {

Software/PC_Application/LibreVNA-GUI/Traces/tracewaterfall.h

@@ -44,9 +44,6 @@ protected slots:
 private slots:
     void updateYAxis();
 private:
-    // color scale, input value from 0.0 to 1.0
-    QColor getColor(double scale);
-
     enum class Direction {
         TopToBottom,
         BottomToTop,

Software/PC_Application/LibreVNA-GUI/Util/prbs.cpp

@@ -0,0 +1,43 @@
+#include "prbs.h"
+
+#include <array>
+
+PRBS::PRBS(unsigned int bits)
+{
+    this->bits = bits;
+
+    // from https://www.eetimes.com/tutorial-linear-feedback-shift-registers-lfsrs-part-1/
+    const std::array<unsigned int, 12> polynoms = {{
+        0x00000000,
+        0x00000000,
+        0x00000003,
+        0x00000005,
+        0x00000009,
+        0x00000012,
+        0x00000021,
+        0x00000041,
+        0x0000008E,
+        0x00000108,
+        0x00000204,
+        0x00000402,
+    }};
+    if(bits < 2 || bits >= polynoms.size()) {
+        throw std::runtime_error("Bit size not supported");
+    }
+    polynom = polynoms[bits];
+    shiftReg = 0xFFFFFFFF;
+}
+
+bool PRBS::next()
+{
+    bool newbit = false;
+    unsigned int mask = 0x01;
+    for(unsigned int i=0;i<bits;i++) {
+        if(polynom & mask & shiftReg) {
+            newbit = !newbit;
+        }
+        mask <<= 1;
+    }
+    shiftReg = (shiftReg << 1) | (newbit ? 0x01 : 0x00);
+    return newbit;
+}

Software/PC_Application/LibreVNA-GUI/Util/prbs.h

@@ -0,0 +1,18 @@
+#ifndef PRBS_H
+#define PRBS_H
+
+
+class PRBS
+{
+public:
+    PRBS(unsigned int bits);
+
+    bool next();
+
+private:
+    unsigned int bits;
+    unsigned int shiftReg;
+    unsigned int polynom;
+};
+
+#endif // PRBS_H

Software/PC_Application/LibreVNA-GUI/Util/util.cpp

@@ -188,3 +188,16 @@ std::complex<double> Util::addTransmissionLine(std::complex<double> termination_
 
     return Gamma_i;
 }
+
+QColor Util::getIntensityGradeColor(double intensity)
+{
+    if(intensity < 0.0) {
+        return Qt::black;
+    } else if(intensity > 1.0) {
+        return Qt::white;
+    } else if(intensity >= 0.0 && intensity <= 1.0) {
+        return QColor::fromHsv(Util::Scale<double>(intensity, 0.0, 1.0, 240, 0), 255, 255);
+    } else {
+        return Qt::black;
+    }
+}

Software/PC_Application/LibreVNA-GUI/Util/util.h

@@ -88,6 +88,9 @@ namespace Util {
         result1 = (-b + root) / (T(2) * a);
         result2 = (-b - root) / (T(2) * a);
     }
+
+    // intensity color scale, input value from 0.0 to 1.0
+    QColor getIntensityGradeColor(double intensity);
 }
 
 #endif // UTILH_H

Software/PC_Application/LibreVNA-GUI/VNA/vna.cpp

@@ -12,6 +12,7 @@
 #include "CustomWidgets/siunitedit.h"
 #include "Traces/Marker/markerwidget.h"
 #include "Tools/impedancematchdialog.h"
+#include "Tools/eyediagramdialog.h"
 #include "ui_main.h"
 #include "Device/firmwareupdatedialog.h"
 #include "preferences.h"
@@ -182,6 +183,8 @@ VNA::VNA(AppWindow *window, QString name)
     actions.insert(toolsMenu->menuAction());
     auto impedanceMatching = toolsMenu->addAction("Impedance Matching");
     connect(impedanceMatching, &QAction::triggered, this, &VNA::StartImpedanceMatching);
+    auto eyeDiagram = toolsMenu->addAction("Eye Diagram");
+    connect(eyeDiagram, &QAction::triggered, this, &VNA::StartEyeDiagram);
 
     defaultCalMenu = new QMenu("Default Calibration", window);
     assignDefaultCal = defaultCalMenu->addAction("Assign...");
@@ -952,6 +955,14 @@ void VNA::StartImpedanceMatching()
     }
 }
 
+void VNA::StartEyeDiagram()
+{
+    auto dialog = new EyeDiagramDialog(traceModel);
+    if(AppWindow::showGUI()) {
+        dialog->show();
+    }
+}
+
 
 void VNA::SetSweepType(SweepType sw)
 {

Software/PC_Application/LibreVNA-GUI/VNA/vna.h

@@ -81,6 +81,7 @@ public slots:
 private slots:
     void NewDatapoint(VirtualDevice::VNAMeasurement m);
     void StartImpedanceMatching();
+    void StartEyeDiagram();
     // Sweep control
     void SetSweepType(SweepType sw);
     void SetStartFreq(double freq);

Software/PC_Application/LibreVNA-Test/LibreVNA-Test.pro

@@ -40,6 +40,7 @@ SOURCES +=  \
     ../LibreVNA-GUI/SpectrumAnalyzer/spectrumanalyzer.cpp \
     ../LibreVNA-GUI/SpectrumAnalyzer/tracewidgetsa.cpp \
     ../LibreVNA-GUI/Tools/eseries.cpp \
+    ../LibreVNA-GUI/Tools/eyediagramdialog.cpp \
     ../LibreVNA-GUI/Tools/impedancematchdialog.cpp \
     ../LibreVNA-GUI/Tools/parameters.cpp \
     ../LibreVNA-GUI/Traces/Marker/marker.cpp \
@@ -108,6 +109,7 @@ SOURCES +=  \
     ../LibreVNA-GUI/Traces/tracexyplot.cpp \
     ../LibreVNA-GUI/Traces/waterfallaxisdialog.cpp \
     ../LibreVNA-GUI/Traces/xyplotaxisdialog.cpp \
+    ../LibreVNA-GUI/Util/prbs.cpp \
     ../LibreVNA-GUI/Util/util.cpp \
     ../LibreVNA-GUI/VNA/Deembedding/deembedding.cpp \
     ../LibreVNA-GUI/VNA/Deembedding/deembeddingdialog.cpp \
@@ -201,6 +203,7 @@ HEADERS += \
     ../LibreVNA-GUI/SpectrumAnalyzer/spectrumanalyzer.h \
     ../LibreVNA-GUI/SpectrumAnalyzer/tracewidgetsa.h \
     ../LibreVNA-GUI/Tools/eseries.h \
+    ../LibreVNA-GUI/Tools/eyediagramdialog.h \
     ../LibreVNA-GUI/Tools/impedancematchdialog.h \
     ../LibreVNA-GUI/Tools/parameters.h \
     ../LibreVNA-GUI/Traces/Marker/marker.h \
@@ -280,6 +283,7 @@ HEADERS += \
     ../LibreVNA-GUI/Traces/tracexyplot.h \
     ../LibreVNA-GUI/Traces/waterfallaxisdialog.h \
     ../LibreVNA-GUI/Traces/xyplotaxisdialog.h \
+    ../LibreVNA-GUI/Util/prbs.h \
     ../LibreVNA-GUI/Util/util.h \
     ../LibreVNA-GUI/VNA/Deembedding/deembedding.h \
     ../LibreVNA-GUI/VNA/Deembedding/deembeddingdialog.h \
@@ -339,6 +343,7 @@ FORMS += \
     ../LibreVNA-GUI/Device/firmwareupdatedialog.ui \
     ../LibreVNA-GUI/Device/manualcontroldialog.ui \
     ../LibreVNA-GUI/Generator/signalgenwidget.ui \
+    ../LibreVNA-GUI/Tools/eyediagramdialog.ui \
     ../LibreVNA-GUI/Tools/impedancematchdialog.ui \
     ../LibreVNA-GUI/Traces/Marker/markerwidget.ui \
     ../LibreVNA-GUI/Traces/Math/dftdialog.ui \