A broadband resonant cavity antenna using a metamaterial based on double-side identical arrays

This paper presents the design of a broadband resonant cavity antenna (RCA) over the X-band region. A broad radiation bandwidth is obtained with a novel low-profile superstrate using a two-layer metamaterial. The proposed metamaterial superstrate configuration consists of cladding identical patch arrays on a double-side FR4 slab. The metamatereial effect is associated with the transmission resonance. The superstrate interacts with the wideband patch based feed source. The characteristics of the radiation and impedance are focused in order to enhance the antenna performance. The responses as the design parameters of the cavity configuration are studied. The simulation shows good results of antenna radiation with enhanced directivity with a wide band and a flat ripple. The 1-dB radiation bandwidth is 50% and the maximum directivity is 13.5 dBi at the middle frequency of 10 GHz. Also, the impedance bandwidth is as large as 50%.