Theoretical Calculation of the Phase Limit for Transmitarray Unit Cell

This paper presents a theoretical study that establishes the performance limits for a multi-layer transmitarray unit cell. This is the first study to be applicable to unit cells in which the conducting resonators, on the different layers, are shaped differently. The study enables one to account for the effects of dynamically reconfiguring the resonators on certain layers (e.g. through shape change). Specifically, the paper quantifies the range of phase shift values, available from the unit cell, for a given amplitude of S21. The first step in the study was to derive theoretical calculations. The theoretical calculations predict that, for an S21 amplitude of −1 dB, unit cells having three conducting layers can provide a phase shifting range of 360°. It is achieved when the geometries of the resonators on the different layers are varied independently. Then the theoretical calculations have been validated through computer simulation.