Merge pull request #5 from mihtjel/ReferenceSweeps

Reference sweeps

Chart.py

@@ -0,0 +1,54 @@
+#  NanoVNASaver - a python program to view and export Touchstone data from a NanoVNA
+#  Copyright (C) 2019.  Rune B. Broberg
+#
+#  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, either 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 for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+import collections
+from typing import List
+
+from PyQt5 import QtWidgets, QtGui, QtCore
+
+from Marker import Marker
+Datapoint = collections.namedtuple('Datapoint', 'freq re im')
+
+
+class Chart(QtWidgets.QWidget):
+    sweepColor = QtCore.Qt.darkYellow
+    referenceColor : QtGui.QColor = QtGui.QColor(QtCore.Qt.blue)
+    referenceColor.setAlpha(64)
+    data : List[Datapoint] = []
+    reference : List[Datapoint] = []
+    markers: List[Marker] = []
+
+    def setSweepColor(self, color : QtGui.QColor):
+        self.sweepColor = color
+        self.update()
+
+    def setReferenceColor(self, color : QtGui.QColor):
+        self.referenceColor = color
+        self.update()
+
+    def setReference(self, data):
+        self.reference = data
+        self.update()
+
+    def resetReference(self):
+        self.reference = []
+        self.update()
+
+    def setData(self, data):
+        self.data = data
+        self.update()
+
+    def setMarkers(self, markers):
+        self.markers = markers

LogMagChart.py

@@ -32,11 +32,13 @@
 
 from PyQt5 import QtWidgets, QtGui, QtCore
 
+from Chart import Chart
 from Marker import Marker
 
 Datapoint = collections.namedtuple('Datapoint', 'freq re im')
 
-class LogMagChart(QtWidgets.QWidget):
+
+class LogMagChart(Chart):
     def __init__(self, name=""):
         super().__init__()
         self.leftMargin = 30
@@ -51,15 +53,8 @@ def __init__(self, name=""):
         self.setPalette(pal)
         self.setAutoFillBackground(True)
 
-        self.values = []
-        self.frequencies = []
-        self.data : List[Datapoint] = []
-        self.markers : List[Marker] = []
-
         self.marker1Color = QtGui.QColor(255, 0, 20)
         self.marker2Color = QtGui.QColor(20, 0, 255)
-        self.sweepColor   = QtGui.QColor(220, 200, 30, 128)
-
 
     def resizeEvent(self, a0: QtGui.QResizeEvent) -> None:
         self.chartWidth = a0.size().width()-20-self.leftMargin
@@ -80,12 +75,19 @@ def drawChart(self, qp: QtGui.QPainter):
         qp.drawLine(self.leftMargin-5, 20+self.chartHeight, self.leftMargin+self.chartWidth, 20 + self.chartHeight)
 
     def drawValues(self, qp: QtGui.QPainter):
-        if len(self.data) == 0:
+        if len(self.data) == 0 and len(self.reference) == 0:
             return
         pen = QtGui.QPen(self.sweepColor)
         pen.setWidth(2)
         highlighter = QtGui.QPen(QtGui.QColor(20, 0, 255))
         highlighter.setWidth(3)
+        if len(self.data) > 0:
+            fstart = self.data[0].freq
+            fstop = self.data[len(self.data)-1].freq
+        else:
+            fstart = self.reference[0].freq
+            fstop = self.reference[len(self.reference) - 1].freq
+        fspan = fstop-fstart
         # Find scaling
         min = 100
         max = 0
@@ -101,6 +103,21 @@ def drawValues(self, qp: QtGui.QPainter):
                 max = logmag
             if logmag < min:
                 min = logmag
+        for d in self.reference:  # Also check min/max for the reference sweep
+            if d.freq < fstart or d.freq > fstop:
+                continue
+            re = d.re
+            im = d.im
+            re50 = 50 * (1 - re * re - im * im) / (1 + re * re + im * im - 2 * re)
+            im50 = 50 * (2 * im) / (1 + re * re + im * im - 2 * re)
+            # Calculate the reflection coefficient
+            mag = math.sqrt((re50-50)*(re50-50) + im50 * im50)/math.sqrt((re50+50)*(re50+50) + im50 * im50)
+            logmag = -20 * math.log10(mag)
+            if logmag > max:
+                max = logmag
+            if logmag < min:
+                min = logmag
+
         min = 10*math.floor(min/10)
         max = 10*math.ceil(max/10)
         span = max-min
@@ -110,10 +127,6 @@ def drawValues(self, qp: QtGui.QPainter):
         qp.setPen(QtCore.Qt.black)
         qp.drawText(3, 35, str(-min))
         qp.drawText(3, self.chartHeight+20, str(-max))
-        # Draw frequency markers
-        fstart = self.data[0].freq
-        fstop = self.data[len(self.data)-1].freq
-        fspan = fstop-fstart
         # At least 100 px between ticks
         qp.drawText(self.leftMargin-20, 20 + self.chartHeight + 15, LogMagChart.shortenFrequency(fstart))
         ticks = math.floor(self.chartWidth/100)  # Number of ticks does not include the origin
@@ -136,6 +149,22 @@ def drawValues(self, qp: QtGui.QPainter):
             x = self.leftMargin + 1 + round(self.chartWidth/len(self.data) * i)
             y = 30 + round((logmag-min)/span*(self.chartHeight-10))
             qp.drawPoint(int(x), int(y))
+        pen.setColor(self.referenceColor)
+        qp.setPen(pen)
+        for i in range(len(self.reference)):
+            if self.reference[i].freq < fstart or self.reference[i].freq > fstop:
+                continue
+
+            re = self.reference[i].re
+            im = self.reference[i].im
+            re50 = 50 * (1 - re * re - im * im) / (1 + re * re + im * im - 2 * re)
+            im50 = 50 * (2 * im) / (1 + re * re + im * im - 2 * re)
+            # Calculate the reflection coefficient
+            mag = math.sqrt((re50-50)*(re50-50) + im50 * im50)/math.sqrt((re50+50)*(re50+50) + im50 * im50)
+            logmag = -20 * math.log10(mag)
+            x = self.leftMargin + 1 + round(self.chartWidth*(self.reference[i].freq - fstart)/fspan)
+            y = 30 + round((logmag-min)/span*(self.chartHeight-10))
+            qp.drawPoint(int(x), int(y))
         # Now draw the markers
         for m in self.markers:
             if m.location != -1:
@@ -153,26 +182,10 @@ def drawValues(self, qp: QtGui.QPainter):
                 y = 30 + round((logmag - min) / span * (self.chartHeight - 10))
                 qp.drawPoint(int(x), int(y))
 
-    def setValues(self, values, frequencies):
-        self.values = values
-        self.frequencies = frequencies
-        self.update()
-
-    def setData(self, data):
-        self.data = data
-        self.update()
-
-    def setMarkers(self, markers):
-        self.markers = markers
-
     @staticmethod
     def shortenFrequency(frequency):
         if frequency < 50000:
             return frequency
         if frequency < 5000000:
             return str(round(frequency / 1000)) + "k"
-        return str(round(frequency / 1000000, 1)) + "M"
-
-    def setSweepColor(self, color : QtGui.QColor):
-        self.sweepColor = color
-        self.update()
+        return str(round(frequency / 1000000, 1)) + "M"

NanoVNASaver.py

@@ -23,10 +23,12 @@
 import serial
 from PyQt5 import QtWidgets, QtCore, QtGui
 
+import Chart
 from Marker import Marker
 from SmithChart import SmithChart
 from SweepWorker import SweepWorker
 from LogMagChart import LogMagChart
+from Touchstone import Touchstone
 
 Datapoint = collections.namedtuple('Datapoint', 'freq re im')
 
@@ -45,26 +47,34 @@ def __init__(self):
         self.serial = serial.Serial()
 
         self.dataLock = threading.Lock()
-        self.values = []
-        self.frequencies = []
         self.data : List[Datapoint] = []
         self.data21 : List[Datapoint] = []
+        self.referenceS11data : List[Datapoint] = []
+        self.referenceS21data : List[Datapoint] = []
+
         self.markers = []
 
         self.serialPort = "COM11"
         # self.serialSpeed = "115200"
 
         self.color = QtGui.QColor(160, 140, 20, 128)
+        self.referenceColor = QtGui.QColor(0, 0, 255, 32)
 
         self.setWindowTitle("NanoVNA Saver")
         layout = QtWidgets.QGridLayout()
         self.setLayout(layout)
 
-        self.smithChart = SmithChart("S11")
+        self.s11SmithChart = SmithChart("S11")
         self.s21SmithChart = SmithChart("S21")
         self.s11LogMag = LogMagChart("S11 Return Loss")
         self.s21LogMag = LogMagChart("S21 Gain")
 
+        self.charts : List[Chart] = []
+        self.charts.append(self.s11SmithChart)
+        self.charts.append(self.s21SmithChart)
+        self.charts.append(self.s11LogMag)
+        self.charts.append(self.s21LogMag)
+
         left_column = QtWidgets.QVBoxLayout()
         right_column = QtWidgets.QVBoxLayout()
 
@@ -135,7 +145,7 @@ def __init__(self):
         marker_control_layout.addRow(label, layout)
         self.markers.append(marker2)
 
-        self.smithChart.setMarkers(self.markers)
+        self.s11SmithChart.setMarkers(self.markers)
         self.s21SmithChart.setMarkers(self.markers)
 
         self.marker1label = QtWidgets.QLabel("")
@@ -219,6 +229,48 @@ def __init__(self):
 
         left_column.addSpacerItem(QtWidgets.QSpacerItem(1, 1, QtWidgets.QSizePolicy.Fixed, QtWidgets.QSizePolicy.Expanding))
 
+        ################################################################################################################
+        #  Reference control
+        ################################################################################################################
+
+        reference_control_box = QtWidgets.QGroupBox()
+        reference_control_box.setMaximumWidth(400)
+        reference_control_box.setTitle("Reference sweep")
+        reference_control_layout = QtWidgets.QFormLayout(reference_control_box)
+
+        btnSetReference = QtWidgets.QPushButton("Set current as reference")
+        btnSetReference.clicked.connect(self.setReference)
+        self.btnResetReference = QtWidgets.QPushButton("Reset reference")
+        self.btnResetReference.clicked.connect(self.resetReference)
+        self.btnResetReference.setDisabled(True)
+        self.btnReferenceColorPicker = QtWidgets.QPushButton("█")
+        self.btnReferenceColorPicker.setFixedWidth(20)
+        self.setReferenceColor(self.referenceColor)
+        self.btnReferenceColorPicker.clicked.connect(lambda: self.setReferenceColor(
+            QtWidgets.QColorDialog.getColor(self.referenceColor, options=QtWidgets.QColorDialog.ShowAlphaChannel)))
+
+        set_reference_layout = QtWidgets.QHBoxLayout()
+        set_reference_layout.addWidget(btnSetReference)
+        set_reference_layout.addWidget(self.btnReferenceColorPicker)
+        reference_control_layout.addRow(set_reference_layout)
+        reference_control_layout.addRow(self.btnResetReference)
+
+        self.referenceFileNameInput = QtWidgets.QLineEdit("")
+        btnReferenceFilePicker = QtWidgets.QPushButton("...")
+        btnReferenceFilePicker.setMaximumWidth(25)
+        btnReferenceFilePicker.clicked.connect(self.pickReferenceFile)
+        referenceFileNameLayout = QtWidgets.QHBoxLayout()
+        referenceFileNameLayout.addWidget(self.referenceFileNameInput)
+        referenceFileNameLayout.addWidget(btnReferenceFilePicker)
+
+        reference_control_layout.addRow(QtWidgets.QLabel("Filename"), referenceFileNameLayout)
+
+        btnImportReference = QtWidgets.QPushButton("Import reference file")
+        btnImportReference.clicked.connect(self.loadReferenceFile)
+        reference_control_layout.addRow(btnImportReference)
+
+        left_column.addWidget(reference_control_box)
+
         ################################################################################################################
         #  Serial control
         ################################################################################################################
@@ -250,7 +302,6 @@ def __init__(self):
         file_control_box.setMaximumWidth(400)
         file_control_layout = QtWidgets.QFormLayout(file_control_box)
         self.fileNameInput = QtWidgets.QLineEdit("")
-        self.fileNameInput.setAlignment(QtCore.Qt.AlignRight)
         btnFilePicker = QtWidgets.QPushButton("...")
         btnFilePicker.setMaximumWidth(25)
         btnFilePicker.clicked.connect(self.pickFile)
@@ -277,7 +328,7 @@ def __init__(self):
         self.lister = QtWidgets.QPlainTextEdit()
         self.lister.setFixedHeight(100)
         charts = QtWidgets.QGridLayout()
-        charts.addWidget(self.smithChart, 0, 0)
+        charts.addWidget(self.s11SmithChart, 0, 0)
         charts.addWidget(self.s21SmithChart, 1, 0)
         charts.addWidget(self.s11LogMag, 0, 1)
         charts.addWidget(self.s21LogMag, 1, 1)
@@ -291,6 +342,10 @@ def __init__(self):
         self.worker.signals.updated.connect(self.dataUpdated)
         self.worker.signals.finished.connect(self.sweepFinished)
 
+    def pickReferenceFile(self):
+        filename, _ = QtWidgets.QFileDialog.getOpenFileName(directory=self.referenceFileNameInput.text(), filter="Touchstone Files (*.s1p *.s2p);;All files (*.*)")
+        self.referenceFileNameInput.setText(filename)
+
     def pickFile(self):
         filename, _ = QtWidgets.QFileDialog.getSaveFileName(directory=self.fileNameInput.text(), filter="Touchstone Files (*.s1p *.s2p);;All files (*.*)")
         self.fileNameInput.setText(filename)
@@ -473,7 +528,7 @@ def dataUpdated(self):
                     im50str = "+ j" + str(round(im50, 3))
                 self.marker2label.setText(str(round(re50, 3)) + im50str + " VSWR: 1:" + str(round(vswr, 3)))
 
-            self.smithChart.setData(self.data)
+            self.s11SmithChart.setData(self.data)
             self.s21SmithChart.setData(self.data21)
             self.s11LogMag.setData(self.data)
             self.s21LogMag.setData(self.data21)
@@ -586,10 +641,8 @@ def setSweepColor(self, color : QtGui.QColor):
             p.setColor(QtGui.QPalette.ButtonText, color)
             self.btnColorPicker.setPalette(p)
 
-            self.smithChart.setSweepColor(color)
-            self.s21SmithChart.setSweepColor(color)
-            self.s11LogMag.setSweepColor(color)
-            self.s21LogMag.setSweepColor(color)
+            for c in self.charts:
+                c.setSweepColor(color)
 
     @staticmethod
     def formatFrequency(freq):
@@ -626,4 +679,40 @@ def parseFrequency(freq : str):
             return int(round(multiplier * f))
         except ValueError:
             # Okay, we couldn't parse this however much we tried.
-            return -1
+            return -1
+
+    def setReference(self):
+        self.setReference(self.data, self.data21)
+
+    def setReference(self, s11data, s21data):
+        self.referenceS11data = s11data
+        self.s11SmithChart.setReference(s11data)
+        self.s11LogMag.setReference(s11data)
+
+        self.referenceS21data = s21data
+        self.s21SmithChart.setReference(s21data)
+        self.s21LogMag.setReference(s21data)
+        self.btnResetReference.setDisabled(False)
+
+    def resetReference(self):
+        self.referenceS11data = []
+        self.referenceS21data = []
+        for c in self.charts:
+            c.resetReference()
+        self.btnResetReference.setDisabled(True)
+
+    def setReferenceColor(self, color):
+        if color.isValid():
+            self.referenceColor = color
+            p = self.btnReferenceColorPicker.palette()
+            p.setColor(QtGui.QPalette.ButtonText, color)
+            self.btnReferenceColorPicker.setPalette(p)
+
+            for c in self.charts:
+                c.setReferenceColor(color)
+
+    def loadReferenceFile(self):
+        filename = self.referenceFileNameInput.text()
+        t = Touchstone(filename)
+        t.load()
+        self.setReference(t.s11data, t.s21data)