Updates from testing 6/19, added proper range scaling for range-doppler plots,...

Updates from testing 6/19, added proper range scaling for range-doppler plots, started implementing cable length corrections

pyratk/acquisition/virtual_daq.py

@@ -100,7 +100,7 @@ class VirtualDAQ(daq.DAQ):
             raise Exception('No dataset loaded.')
 
 
-    def get_samples(self, stride=1, loop=-1, playback_speed=30):
+    def get_samples(self, stride=1, loop=-1, playback_speed=0.25):
         """Read sample from dataset at sampled speed, or one-by-one."""
         if self.ds:
             # Read in samples from dataset
@@ -114,7 +114,7 @@ class VirtualDAQ(daq.DAQ):
 
             # Delay by sample period
             if loop == -1 or loop == 1:
-                time.sleep(self.sample_period * playback_speed)
+                time.sleep(self.sample_period / playback_speed)
             elif loop == 0:
                 print('Stepped:', stride)
             else:

pyratk/radars/radar.py

@@ -73,6 +73,8 @@ class Receiver(object):
         self.slow_fft_window_type = slow_fft_window_type
         self.slow_fft_len = slow_fft_len
 
+        self.pulse = self.transmitter.pulses[0]
+
         self.datacube = DataCube(self)
 
         self.init_data()
@@ -88,6 +90,10 @@ class Receiver(object):
         self.fast_fft_data = np.ones(self.fast_fft_size)
         self.fft_mat = np.ones((self.fast_fft_size, self.slow_fft_size))
 
+        self.freq_to_range = -(self.pulse.delay / self.pulse.bw) * 3e8
+
+        self.freq_correction = 5.5 / self.freq_to_range
+
         self.fast_fmax = 0
         self.slow_fmax = 0
 

pyratk/trackers/aps_tracker.py

@@ -29,6 +29,8 @@ class ApsTracker(object):
         self.pulse = self.receiver_array[0].transmitter.pulses[0]
         self.chirp_rate = self.pulse.bw / self.pulse.delay
 
+        self.baseline=1.18 # m
+
         # Configure control signals
         self.connect_control_signals()
 
@@ -58,7 +60,7 @@ class ApsTracker(object):
         f=np.linspace(-50000,50000,num=var0.size-1)
         r_d0=np.abs(f[np.argmax(var0)]*3e8/self.chirp_rate/2)
         r_d1=np.abs(f[np.argmax(var1)]*3e8/self.chirp_rate/2)
-        theta=np.arcsin((r_d0-r_d1)/0.3864)+0.5*np.pi
+        theta=np.arcsin((r_d0-r_d1)/self.baseline)+0.5*np.pi
         R=0.5*(r_d0+r_d1)
 
         # loc is cylindrical (R, theta, Z), but Z is ignored by plot

pyratk/widgets/range_doppler_widget.py

@@ -15,7 +15,7 @@ from matplotlib import cm       # Used for colormaps
 
 
 class RangeDopplerWidget(pg.PlotWidget):
-    def __init__(self, receiver, xrange=[-50,50], yrange=[-15e3,0], showMeters=False):
+    def __init__(self, receiver, xrange=[-50,50], yrange=[-10e3,0], showMeters=True):
         super().__init__()
 
         # Copy arguments to member variables
@@ -28,7 +28,9 @@ class RangeDopplerWidget(pg.PlotWidget):
             self.source.sample_chunk_size / self.source.sample_rate
 
         self.freq_to_vel = (3e8 / self.pulse.fc) / 2
-        self.freq_to_range = (self.pulse.delay / self.pulse.bw) * 3e8
+        self.freq_to_range = -(self.pulse.delay / self.pulse.bw) * 3e8 / 2
+
+        self.offset_freq = 5.5 / self.freq_to_range * 2
 
         self.xrange = xrange
         self.yrange = yrange
@@ -55,7 +57,7 @@ class RangeDopplerWidget(pg.PlotWidget):
 
         # set colormap
         self.img.setLookupTable(lut)
-        self.img.setLevels([-80, 10]) # Good for drone
+        self.img.setLevels([-90, -10]) # Good for drone
         #self.img.setLevels([-10, 20]) # Good for drone
 
         self.rescale()
@@ -66,14 +68,13 @@ class RangeDopplerWidget(pg.PlotWidget):
         else:
             self.setLabel('left', 'Frequency', units='Hz')
             self.setLabel('bottom', 'Frequency', units='Hz')
+            # Invert y-axis so negative is "up" (corresponds with range)
+            self.getViewBox().invertY(True)
         self.showGrid(x=True, y=True)
 
         left_axis=self.getAxis('left')
         left_axis.setGrid(255)
 
-        # Invert y-axis so negative is "up" (corresponds with range)
-        self.getViewBox().invertY(True)
-
         self.img.setCompositionMode(pg.QtGui.QPainter.CompositionMode_Plus)
 
         # self.setLabel('right', 'Range', 'm')
@@ -126,20 +127,25 @@ class RangeDopplerWidget(pg.PlotWidget):
             self.source.sample_chunk_size / self.source.sample_rate
 
         if self.showMeters:
-            self.img.scale(self.receiver.slow_bin_size * self.freq_to_vel,
-                           self.receiver.fast_bin_size * self.freq_to_range)
+            slow_scale = self.receiver.slow_bin_size * self.freq_to_vel
+            fast_scale = self.receiver.fast_bin_size * self.freq_to_range
+            yrange = np.array(self.yrange) * self.freq_to_range
+            slow_limit = self.receiver.slow_bin_size * self.receiver.slow_fft_size / 4 * self.freq_to_vel
         else:
-            self.img.scale(self.receiver.slow_bin_size,
-                           self.receiver.fast_bin_size)
+            slow_scale = self.receiver.slow_bin_size
+            fast_scale = self.receiver.fast_bin_size
+            yrange = self.yrange
+            slow_limit = self.receiver.slow_bin_size * self.receiver.slow_fft_size / 4
 
-        self.setRange(disableAutoRange=True, yRange=np.array(self.yrange))
 
-        self.img.translate(-np.array(self.receiver.fft_mat.shape[1]) / (2 * self.downsample),
-            -np.array(self.receiver.fft_mat.shape[0]) / (2 * self.downsample))
+        self.img.scale(slow_scale, fast_scale)
 
+        self.setRange(disableAutoRange=True, yRange=np.array(yrange))
 
-        # TODO: why is the /4 instead of /2??
-        slow_limit = self.receiver.slow_bin_size * self.receiver.slow_fft_size / 4
+        offset_bins = self.offset_freq / self.receiver.fast_fft_size
+
+        self.img.translate(-np.array(self.receiver.fft_mat.shape[1]) / (2 * self.downsample),
+            -np.array(self.receiver.fft_mat.shape[0]) / (2 * self.downsample))
 
         self.setLimits(
             xMin=-slow_limit, xMax=slow_limit)