better tx tone

README.md

@@ -39,7 +39,9 @@ Without this, you'll be limited to S11 and uncalibrated S21 measurements (with r
 There's nothing special about this particular board, if you want more than 4 ports you can make your own pretty easily. You just need 3 SPxT switches. Note that these switches will see tons of cycles so avoid mechanical switches.
 - SMA cables
 
-### Pluto Modification
+### Pluto Configuration
+
+Most of my testing is with Pluto firmware [v0.39](https://github.com/analogdevicesinc/plutosdr-fw/releases/tag/v0.39) though this may work with other firmware versions. Instructions for upgrading firmware are on the [Analog Devices wiki](https://wiki.analog.com/university/tools/pluto/users/firmware).
 
 We need two receive channels on the SDR. If you have a Pluto+ that should already be configured and you can skip this step.
 

charon_vna/gui.py

@@ -14,6 +14,8 @@ from numpy import typing as npt
 from PySide6.QtGui import QAction, QKeySequence
 from PySide6.QtWidgets import (
     QApplication,
+    QFileDialog,
+    QInputDialog,
     QMainWindow,
     QMenu,
     QProgressBar,
@@ -21,18 +23,19 @@ from PySide6.QtWidgets import (
     QWidget,
 )
 from skrf import plotting as rf_plt
+from vna import Charon
 
 from charon_vna.gui_helpers import FlowLayout
 from charon_vna.util import db20, s2vswr
 
-# from vna import Charon
-
 # %%
 DEFAULT_CONFIG = dict(
     frequency=np.arange(1e9, 2e9, 11),  # Hz
     power=-5,  # dB
 )
 
+CONFIG_SUFFIX = ".json"
+
 
 class PlotWidget(QWidget):
     traces: List[Tuple[int | str]]
@@ -157,6 +160,7 @@ class MainWindow(QMainWindow):
         super().__init__()
 
         self.config_path = None
+        self._frequency = np.linspace(1e9, 2e9, 101)  # TODO: read frequency from config
 
         # self.device = Charon("ip:192.168.3.1", frequency=DEFAULT_CONFIG["frequency"])
 
@@ -169,10 +173,10 @@ class MainWindow(QMainWindow):
 
         menu_file = QMenu("&File")
         menubar.addMenu(menu_file)
-        action_load_config = QAction("&Open Configuration", self)
-        menu_file.addAction(action_load_config)
-        action_load_config.triggered.connect(self.load_config)
-        action_load_config.setShortcut(QKeySequence("Ctrl+O"))
+        action_open_config = QAction("&Open Configuration", self)
+        menu_file.addAction(action_open_config)
+        action_open_config.triggered.connect(self.open_config)
+        action_open_config.setShortcut(QKeySequence("Ctrl+O"))
         action_save_config = QAction("&Save Configuration", self)
         menu_file.addAction(action_save_config)
         action_save_config.triggered.connect(self.save_config)
@@ -186,7 +190,7 @@ class MainWindow(QMainWindow):
         menubar.addMenu(menu_stimulus)
         action_set_frequency = QAction("&Frequency", self)
         menu_stimulus.addAction(action_set_frequency)
-        # action_set_frequency.triggered.connect(self.set_frequency)
+        action_set_frequency.triggered.connect(self.set_frequency)
         action_set_power = QAction("&Power", self)
         menu_stimulus.addAction(action_set_power)
         # action_set_power.triggered.connect(self.set_power)
@@ -230,24 +234,51 @@ class MainWindow(QMainWindow):
 
     def saveas_config(self) -> None:
         print("Prompting for save path...")
-        # TODO: prompt for config path
-        self.config_path = Path(__file__).parent / "config.json"
+        dialog = QFileDialog(self)
+        dialog.setDefaultSuffix(CONFIG_SUFFIX)
+        dialog.setAcceptMode(QFileDialog.AcceptMode.AcceptSave)
+        if dialog.exec():
+            config_path = Path(dialog.selectedFiles()[0])
+            print(config_path)
+            if config_path.suffix != CONFIG_SUFFIX:
+                raise ValueError(
+                    f"{config_path.name} is not a valid configuration file. Must have extension {CONFIG_SUFFIX}"
+                )
+            self.config_path = config_path
             print(f"Config path is now {self.config_path.resolve()}")
+
             self.save_config()
 
+    def open_config(self) -> None:
+        print("Prompting for load path...")
+        dialog = QFileDialog(self)
+        dialog.setNameFilter(f"*{CONFIG_SUFFIX}")
+        dialog.setAcceptMode(QFileDialog.AcceptMode.AcceptOpen)
+        if dialog.exec():
+            config_path = Path(dialog.selectedFiles()[0])
+            print(config_path)
+            if config_path.suffix != CONFIG_SUFFIX:
+                raise ValueError(
+                    f"{config_path.name} is not a valid configuration file. Must have extension {CONFIG_SUFFIX}"
+                )
+            self.config_path = config_path
+            print(f"Config path is now {self.config_path.resolve()}")
+
+            self.load_config(self.config_path)
+
     def save_config(self) -> None:
         if self.config_path is None:
             self.saveas_config()
         else:
-            print(f"saving config to {self.config_path.resolve()}")
+            print(f"Saving config to {self.config_path.resolve()}")
             # TODO: save config
 
-    def load_config(self) -> None:
-        print("loading config")
+    def load_config(self, path: Path) -> None:
+        print(f"Loading config from {path}...")
         # TODO: load config
 
     def generate_sim_data(self) -> None:
-        coords = {"frequency": np.linspace(1e9, 2e9, 101), "m": [1], "n": [1]}
+        coords = {"frequency": self._frequency, "m": [1], "n": [1]}
         shape = tuple(len(v) for v in coords.values())
         data = xr.DataArray(
             ((-1 + 2 * np.random.rand(*shape)) + 1j * (-1 + 2 * np.random.rand(*shape))) / np.sqrt(2),
@@ -258,6 +289,20 @@ class MainWindow(QMainWindow):
         for plot in self.plots:
             plot.update_plot(data)
 
+    def set_frequency(self, *, frequency: npt.ArrayLike | None = None):
+        print(frequency)
+        if frequency is None:
+            start, ok = QInputDialog.getDouble(
+                self, "Start Frequency", "Start Frequency", minValue=30e6, maxValue=6e9, value=1e9
+            )
+            stop, ok = QInputDialog.getDouble(
+                self, "Stop Frequency", "Stop Frequency", minValue=30e6, maxValue=6e9, value=2e9
+            )
+            points, ok = QInputDialog.getInt(self, "Points", "Points", minValue=2, value=101)
+            frequency = np.linspace(start, stop, points)
+        # Currently does not support zero span
+        self._frequency = frequency
+
 
 def main() -> None:
     app = QApplication(sys.argv)

charon_vna/vna.py

@@ -4,7 +4,8 @@ from pathlib import Path
 from typing import Any, Dict, Tuple
 
 import adi
-import iio
+
+# import iio
 import numpy as np
 import skrf as rf
 import xarray as xr
@@ -140,8 +141,9 @@ class Charon:
         self.set_output_power(power)
         self.sdr.tx_lo = int(frequency - self.FREQUENCY_OFFSET)
         self.sdr.tx_cyclic_buffer = True
-        # self.sdr.tx(generate_tone(f=self.FREQUENCY_OFFSET, fs=self.sdr.sample_rate))
-        self.sdr.dds_single_tone(self.FREQUENCY_OFFSET, scale=0.9, channel=0)
+        # For some reason the pluto's DDS has truly horrendous phase noise to the point where it looks modulated
+        self.sdr.tx(generate_tone(f=self.FREQUENCY_OFFSET, fs=self.sdr.sample_rate))
+        # self.sdr.dds_single_tone(self.FREQUENCY_OFFSET, scale=0.9, channel=0)
 
     def _rx(self, count: int = 1, fc: float | None = None) -> npt.ArrayLike:
         if count < 1:
@@ -228,6 +230,10 @@ class Charon:
         return s
 
 
+# %%
+if __name__ == "__main__":
+    pass
+
     # %%
     sdr = Charon("ip:192.168.3.1", frequency=np.linspace(1e9, 1.1e9, 11))
 
@@ -287,7 +293,6 @@ plt.gca().xaxis.set_major_formatter(EngFormatter())
     plt.grid(True)
     plt.show()
 
-
     # %%
     s = sdr.vna_capture(frequency=np.linspace(70e6, 200e6, 101))
 
@@ -322,7 +327,6 @@ if reference_sparams is not None:
 
     plt.show()
 
-
     # %% SOL calibration
     cal_frequency = np.linspace(70e6, 600e6, 101)
     ideal_cal_frequency = rf.Frequency(np.min(cal_frequency), np.max(cal_frequency), len(cal_frequency))
@@ -343,7 +347,6 @@ calibration = rf.calibration.OnePort(
         [cal_ideal.short(), cal_ideal.open(), cal_ideal.load(0)],
     )
 
-
     # %%
     s = sdr.vna_capture(frequency=cal_frequency)