From the viewpoint of minimum-detectable-signal or radar-maximum-range theory, the number of pulses received from a target during one scan of the radar antenna is an important quantity. This has usually been arbitrarily taken to be the number occurring between half-power points of the beam. A mathematical analysis of the 'integration' effect for the train of pulses of varying amplitude received when the antenna beam shape is Gaussian shows that optimum results are obtained when the integration is performed over an angle equal to about 0.84 times the half-power (one-way) beamwidth. The signal-to-noise ratio obtained by this integration is equivalent to that of a rectangular-shaped beam of 0.47 times the half-power width of a Gaussian-shaped beam. Thus the number of pulses received is 0.47 times the number usually assumed. This corresponds to a reduction in calculated system sensitivity of about 1.6 db. (Author)
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