Novel Compact High-Gain Wideband Filtering Metasurface Antenna

A novel compact, high-gain and wideband filtering metasurface antenna (MSA) is firstly proposed in this paper. A folded V-shaped slot and a defected ground structure (DGS) are respectively etched on the top and bottom layers of each metasurface unit for providing lower-edge radiation nulls. In addition, four parasitic patches are loaded around the metasurface (MS) structures on the same layer to achieve upper-edge radiation nulls and simultaneously introduce extra resonances for wide passband. As a result, a good filtering response including high out-of-band suppressions and wideband high-gain directional radiations are realized. Good agreement is observed between the simulated and measured results, demonstrating the good performance with 10-dB impedance bandwidth of about 20%, high average gain of over 8 dBi, maximum aperture efficiency of about 90%, and high out-of-band suppression level of about 20 dB. Due to no extra filtering circuits, the proposed filtering antenna exhibits a very compact size (0.07 λ₀×0.07 λ₀×0.04 λ₀), especially a very low profile.