Design Methodology for Phased Subarray Antennas with Optimized Element Phase Control

A simple yet practical method of grating lobe suppression for phase steered subarray antennas is proposed. In case of more than a certain steering angle, typical subarray configurations generate undesirable grating lobes in the array pattern. Placing additional phase delay at one of antenna elements in subarrays creates distortions in an array pattern of subarrays and shifted nulls in the array pattern cancel corresponding grating lobes that appear at the full array level. The concept introduced in this paper can be used for the increase in scan range of the subarray antenna system.