Each cell receives power from every asset in range using free-space path loss: Pr = Pt + Gt − FSPL(d, f) [dBm] where FSPL = 20·log₁₀(d_km) + 20·log₁₀(f_MHz) + 32.45 dB. Terrain masking uses a ray-march LOS check with Fresnel knife-edge diffraction for partial occlusion. Height above ground raises the effective radio horizon. Directional assets apply a Gaussian beam taper: G(Δθ) = G_max − 12·(Δθ/θ_3dB)² [dB]

Passive acoustic sensors use spherical spreading + atmospheric absorption: TL = 20·log₁₀(r_m) + α·r_km [dB] Received level RL = SL − TL. Terrain shadow is a hard cutoff (no Fresnel diffraction for sound).

1. Place assets from the side trays — drag or click to grid.
2. Press Tab or click Heatmap to toggle the aggregated coverage map.
3. Select a mode from the dropdown (Signal · N-Asset · JSR · Radar · Comms · Acoustic).
4. Use Alt+click on any grid cell to probe exact signal levels from all assets.
5. Switch to Individual mode to see per-asset range circles and directional wedges.
6. Enable Terrain layer + LOS to see how terrain blocks signal.