Radar Observer · Limitations — Multiple Echoes
Multiple echoes (a row of echoes at equal range intervals beyond a close, large target) are caused by:
- ASecond-trace returns
- BRain attenuation
- CThe signal bouncing back and forth between own ship and a nearby large target (e.g., a passing ship)✓ Correct
- DSide lobes
Explanation
When a large target is close, the pulse can reflect repeatedly between it and own ship's side, producing a line of progressively weaker echoes at multiples of the true range. The first (nearest) echo is the real one; the rest are spurious and fade as the geometry changes.
Authority: Bowditch (Pub. No. 9), Radar Limitations
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