
TARGET DETECTION
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increases in signal strength. The term 'differentiation' is
mathematical in origin and essentially means to measure
the rate of change of some quantity. The theoretical
principle of operation is illustrated by Figure 3.44.
Figure 3.44 (a) and (b) show the effect of varying degrees
of differentiation on a single idealized rectangular pulse,
while Figure 3.44 (c) shows three idealized rectangular
echoes which overlap one another, saturate the receiver
and hence are representative of the masking effect of rain
clutter. The first pulse represents the rain echo which
returns immediately ahead of the target response and the