A metasurface-enabled low-profile wearable antenna

In this paper, we present the design, fabrication, and experimental validation of a low-profile and compact metasurface-based conformal wearable antenna operating in the medical body area network (MBAN) band. In particular, a metal backed finite-sized metasurface consisting of a two by two array of I-shaped resonators was employed to replace the conventional ground plane, which enables a low-profile and unidirectionally radiating antenna when it is integrated with a planar monopole placed on top. The resulting integrated conformal antenna is only 0.028 λ₀ thick with a footprint of around 0.15 λ₀², all while accomplishing a broadside gain higher than 6 dBi, a front-to-back ratio larger than 23 dB, and a VSWR <; 2 bandwidth of around 5.5%. The antenna performance is well maintained with the presence of human body loading, making it highly useful for various wearable systems.