Design of an Open Resonator Antenna using True Time Delay Metasurfaces

This paper presents a design of an open resonator antenna (ORA) that utilizes a specially designed metasurface as its ground plane. The purpose of the introduction of the designed planar metasurface is to realize a spherical groundlike performance, which has proven to be an alternate solution for enhancing the gain bandwidth of the ORA. The designed metasurface utilizes the concept of miniaturized frequency selective surface (MEFSS) and provides time delays on its aperture to produce the spherical ground-like response from 12 GHz to 16 GHz. The proposed metasurface-enabled ORA achieves several benefits that outperform other alternatives i.e. spherical ground or flat ground.It realizes the spherical ground-like performance with planar structure; it reduces the cavity height, and also maintains the wide 3dB gain bandwidth, 20%, with a peak gain of 16.53 dB. Also, the impedance matching is not affected by the introduction of the MEFSS inside the cavity. Therefore, the proposed ORA provides an alternative solution with enhanced 3dB gain-bandwidth and lower cavity profile, which is useful for modern communication systems.