Reflectarray with arbitrarily shaped elements having four-axial symmetry

This paper proposes the design method of such elements by using the genetic algorithm(GA). In design of a reflectarray, to reduce a phase error on the aperture, we need to find a group of elements with arbitrary reflection phase value over the range of 360 degrees. Besides, it is desirable that their elements have a low cross-polarization and dual-polarization property to enhance antenna performance. In optimization design the reflection property of arbitrarily shaped elements was improved by considering their symmetry. Then, we verified effectiveness of the proposed elements from the radiation pattern of the designed reflectarray antenna numerically and experimentally.