SIW-Based Reflectarray Cell as a Means of Reducing Local Periodicity Approximation Errors

Abstract

A new reflectarray unit cell based on a SIW cavity resonator is presented at 18.7 GHz. It features a full cycle of phase shifting and low losses with simple manufacturing requirements. By relying on a resonant cavity instead of more typical open resonant elements, inter-cell coupling effects are reduced. This is validated by simulating the cell in a semi-periodic environment. The response of the cell is estimated from its surface fields under plane-wave excitation for different levels of aperiodicity. The same process is followed for a printed patch unit cell, observing that it is significantly more influenced by its environment.