Surrogate‐assisted design of microstrip corporate feeds integrated with linear microstrip array apertures for required sidelobe levels

Abstract

AbstractA systematic computer‐aided design of low‐sidelobe linear microstrip antenna arrays is proposed. It starts from identifying the corporate feed architecture which is optimal for a given excitation taper under constrains imposed on the power splits within the feed. The novelty of the approach includes utilization of a numerically efficient simulation‐based kriging model of unequal split microstrip junctions for implementation of the optimal microstrip feed, and simulation‐based tuning of the excitation taper. The tuning is carried out with surrogate‐assisted optimization which is based on the electromagnetic simulations of an integrated array circuit comprising the aperture and the feed. Additionally, in‐phase excitation of the array aperture radiators is ensured with a simulation‐based correction of the corporate feed microstrip branches. The approach is implemented iteratively to realize the nominal sidelobe level. The approach is demonstrated with design of a 12‐element H‐plane 25‐dB sidelobe level Tschebyscheff array. Experimental validation is provided.