feat(radar): recalibrate visualization engine for high-fidelity diagnostics

Restores sharp target peaks and improves signal clarity in Shenron radar outputs
by optimizing windowing functions and disabling smoothing-heavy interpolation.

- radar_processor.py: Switched windowing from Hann to Blackman-Harris for range
  and velocity processing to achieve deeper sidelobe rejection (-92 dB) and
  suppress horizontal artifacts.
- test_shenron.py: Replaced 'bicubic' interpolation with 'nearest' for Range-Doppler
  (RD) and CFAR maps to restore diagnostic clarity and prevent target blurring.
- config.yaml: Removed hardcoded RD plot limits (xRange/yRange) to ensure the
  renderer utilizes the true physical axis (e.g., ±26.8 m/s) derived from hardware specs.
- Added technical comments explaining the trade-off between main-lobe width and
  dynamic range in the new DSP windowing.

scripts/ISOLATE/sim_radar_utils/config.yaml

@@ -69,8 +69,9 @@ Visualize:
     xUnit: "m"
     yLabel: "Velocity"
     yUnit: "m/s"
-    xRange: [-8, 8]        # Doppler Velocity limits [m/s]
-    yRange: [0, 120]         # Range limits [m]
+    # xRange and yRange deliberately NOT set here — the renderer uses the true
+    # physical Doppler axis (±26.8 m/s for AWRL1432) computed from chirp_rep.
+    # DO NOT add xRange overrides without resetting the axis in test_shenron.py.
     winSize: [500, 400]
     pos: [600, 50]
   radarPCD:

scripts/ISOLATE/sim_radar_utils/radar_processor.py

@@ -22,10 +22,13 @@ cfarCfg = config['CFAR']
 class RadarProcessor:
     def __init__(self):
         # radar data will be shaped as (# of chirp, # of sample, # of antenna)
-        self.rangeWin = np.tile(signal.windows.hann(radarCfg['N']), (radarCfg['Np'], radarCfg['NrChn'], 1))
+        # Blackman-Harris window: Deepest sidelobe rejection (-92 dB). 
+        # Used to suppress the horizontal "astigmatism" sidelobe lines at the 
+        # cost of a broader main-lobe (slightly less range resolution).
+        self.rangeWin = np.tile(signal.windows.blackmanharris(radarCfg['N']), (radarCfg['Np'], radarCfg['NrChn'], 1))
         self.rangeWin = np.transpose(self.rangeWin, (2, 0, 1))
 
-        self.velWin = np.tile(signal.windows.hann(radarCfg['Np']), (radarCfg['N'], radarCfg['NrChn'], 1))
+        self.velWin = np.tile(signal.windows.blackmanharris(radarCfg['Np']), (radarCfg['N'], radarCfg['NrChn'], 1))
         self.velWin = np.transpose(self.velWin, (0, 2, 1))
 
         rangeRes = fftCfg['c0'] / (2*(radarCfg['fStop'] - radarCfg['fStrt']))

scripts/test_shenron.py

@@ -307,8 +307,8 @@ def run_testbench(iter_name):
             display_limit_cfg = 120.0
             
             render_engines[r_type] = {
-                'rd': FastHeatmapEngine(extent=[-max_vel_cfg, max_vel_cfg, 0, max_r_cfg], cmap='viridis', title=f'{r_type.upper()} Range-Doppler', xlabel='Doppler Velocity [m/s]', ylabel='Range [m]', ylim=[0, 120], interpolation='bicubic'),
-                'cfar': FastHeatmapEngine(extent=[-max_vel_cfg, max_vel_cfg, 0, max_r_cfg], cmap='plasma', title=f'{r_type.upper()} CFAR Noise Threshold', xlabel='Doppler Velocity [m/s]', ylabel='Range [m]', ylim=[0, 120], interpolation='bicubic'),
+                'rd': FastHeatmapEngine(extent=[-max_vel_cfg, max_vel_cfg, 0, max_r_cfg], cmap='viridis', title=f'{r_type.upper()} Range-Doppler', xlabel='Doppler Velocity [m/s]', ylabel='Range [m]', ylim=[0, 120], interpolation='nearest'),
+                'cfar': FastHeatmapEngine(extent=[-max_vel_cfg, max_vel_cfg, 0, max_r_cfg], cmap='plasma', title=f'{r_type.upper()} CFAR Noise Threshold', xlabel='Doppler Velocity [m/s]', ylabel='Range [m]', ylim=[0, 120], interpolation='nearest'),
                 'ra_static': FastHeatmapEngine(extent=[-display_limit_cfg, display_limit_cfg, 0, display_limit_cfg], cmap='jet', vmin=-5, vmax=55, title=f'{r_type.upper()} Range-Azimuth (Absolute)', xlabel='Lateral distance [m]', ylabel='Longitudinal distance [m]', aspect='equal'),
                 'ra_dyn': FastHeatmapEngine(extent=[-display_limit_cfg, display_limit_cfg, 0, display_limit_cfg], cmap='jet', title=f'{r_type.upper()} Range-Azimuth (Dynamic)', xlabel='Lateral distance [m]', ylabel='Longitudinal distance [m]', aspect='equal')
             }