Radar Observer · Performance — Radar Horizon
Compared with the visible (optical) horizon, the radar horizon is generally:
- AShorter, because radar waves bend upward
- BSlightly farther, because radar waves bend with the curvature of the earth more than light✓ Correct
- CExactly the same distance
- DUnrelated to antenna height
Explanation
Standard atmospheric refraction bends radar energy slightly downward, so the radar horizon lies a bit beyond the optical horizon. Both increase with the square root of antenna (or target) height.
Authority: Radar Navigation — Radar Horizon
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