Phase-Bandwidth Enhancement of Microstrip Patch Reflectarray with Cross Slot Loads

A reflectarray antenna composed of microstrip square patches with cross slot loads is introduced. The desired phase delay of reflectarray elements, which are duplicated the same radiating aperture as parabolic backscatters, are determined on the construction of the curvature of a shaped backscatter surface with the help of Snell´s law for beam forming to cover a broad area. The method of moment (MoM) and the infinite-array are applied to calculate reflection phase characteristic. Using this technique, simple two-layer reflectarray with wider phase-bandwidth and compact size is fabricated. The measured results demonstrate that the reflection phase- bandwidth at center frequency of 10 GHz is higher than conventional single-layer reflectarray.