Radar Observer · Limitations — Side-Lobe Echoes
Side-lobe echoes typically appear as:
- ARandom noise at long range
- BA single echo far beyond the target
- CA bearing error of exactly 180°
- DA series of echoes or an arc at the same range as a strong nearby target, spread on either side of its true bearing✓ Correct
Explanation
Energy radiated in the antenna's side lobes can return from a strong close target, painting additional echoes (or a short arc) at the same range but at bearings on each side of the true one. Reducing gain or using STC usually removes them; they are a hazard mainly at short range with strong targets.
Authority: Bowditch (Pub. No. 9), Radar Limitations
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