Optimization of the shape of non-planar electronically scanned arrays for IFF applications via multi-objective invasive weed optimization algorithm

The identify friend or foe antenna is a complement to many radar antennas which allows the discrimination between friendly and hostile targets by receiving identification data. Such antenna must synthesize both a sum and a difference pattern in azimuth to allow target discrimination and must point to the target being inquired, either by mechanical or electronic scanning in azimuth. In this paper, to attain optimal electronic scanning, an array of antennas lying on a generic planar curve is considered. A multi-objective optimization based on the invasive weed optimization algorithm is then applied to the shape of such curve, aimed at maximizing performances. Whereas a conventional linear array of 6 elements can effectively scan ±30°, with respect to broadside, the proposed array, notwithstanding the same number of elements and overall length, can scan ±45° and still synthesize effective sum and difference patterns.