Radar and ARPA Manual

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RADAR AND ARPA MANUAL

3.9.3 Multiple echoes

Multiple echoes are likely when a target is close and

energy bounces back and forth between the hulls of the

target and the observing ship, with some of the energy

entering the antenna at each return (Figure 3.59). The

features of this form of response are that the echoes:

(a) Lie along a single direction.

(b) Are consistently spaced.

(c) Tend to move in accord.

(d) Tend to diminish in strength with the increase of

range.

It should be noted that, while it would seem logical from

Figure 3.59 for this form of response to occur when

vessels are abeam, it has been observed to occur on virtu-

ally al ...