An active metamaterials antenna controleld by RF-MEMS switches

This paper reports an active metamaterials-based CRLH (Composite Right Left Handed) antenna, in which RF-MEMS cantilevers are used as RF switches to reconfigure the radiation patterns. We implement leaky-wave antenna with cascaded metallic patterns of a J-shaped unit that possess an effective electromagnetic homogeneity and tunable metamaterial properties. Owing to the microstrip-based periodic structures that are compatible with micro-machining process, RF-MEMS cantilevers arrays are integrated in each cell to control the electromagnetic boundary conditions. By actuating the RF-MEMS switches between ON and OFF in each unit, the metamaterials properties are tuned and thereby the spatial radiation patterns are correspondingly controlled from backward (around -30°) radiation to forward (around +30°) at a fixed frequency around 9 GHz.