Optimization of antenna array pattern for uniformly excited rectangular array via a thinning method

Abstract

Antenna arrays have various applications, such as radar, military systems, and wireless communications. The performance of the communication system depends heavily on the antenna array design process. The major challenges in designing such arrays are the high sidelobe levels and the enormous number of elements. Recently, optimization techniques that exploit the evolutionary algorithms have been used extensively for thinning the antenna arrays to reduce power consumption and improve the radiation pattern by decreasing the sidelobe levels. However, due to the stochastic nature of the resolution algorithms, achieving a global optimal for such algorithms is not assured. Based on the combination theory, this paper adopts an element-by-element removing strategy for thinning planar arrays. Without loss of generality, a uniformly excited 25 elements rectangular array with isotropic elements is investigated as an example. The proposed thinning method examines all the possible arrangements of the placements of 25 elements in the phased array aperture. The optimum position of elements is selected to achieve the desired characteristics of the radiation pattern. The results show that with the 40% thinning percentage, the same radiation pattern for the full array (without thinning) can be witnessed. Consequently, a considerable reduction in resource utilization can be achieved in terms of power consumption, the number of phase shifters, and the number of attenuators.