Beam Shape Loss and Surveillance Optimization for Pencil Beam Arrays

A radar in its surveillance mode requires the programming of the radar beam in fixed angular increments throughout the surveillance volume. Though radar coverage of the volume is complete, returns from possible targets differing only in angular position generally have unequal signal strengths. This is due to both beam shape and multiple beam coverage. The resulting nonuniformity in signal strength results in a loss factor termed beam shape loss (BSL). This correspondence contains the results of a valid computational procedure for determining this loss factor for the case of an electronically steerable array in a search mode. Results consist of curves showing BSL for a wide range of system parameters and for various target types. In addition, it is shown how optimum search beam locations can be determined from the BSL computations.