Metal-only Multi-beam Fabry-Perot Antenna

Abstract

This paper presents a Fabry-Perot (FP) antenna with azimuthal scanning by beam switching at Ka-band. The system is composed of two stacked layers with circular shape. The bottom layer contains a Reflecting Luneburg Lens (RLL), which serves to generate a plane wave in the top one. In turn, the top layer hosts a Fabry-Perot cavity, which is used to gradually radiate the excited plane wave through a partially reflective surface (PRS), thus, producing a directive beam. Both the RLL and the FP cavity are azimuthally symmetric and allow one to generate identical pencil beams for any azimuthal direction. Moreover, it is possible to scan also in elevation by varying the height of the FP cavity, which provides 2D beam-steering capability. The double-layer approach guarantees the compactness of the device, whereas a full-metal implementation minimizes the propagation losses and renders the structure robust and fit for operation in harsh environments. The proposed system is well-suited for spatial applications, in particular for medium and high-gain antennas integrated in SmallSats and CubeSats.