Compact Monopole Antenna Backed With Fork-Slotted EBG for Wearable Applications

A compact, low-profile ultrawideband directional antenna for a wireless body area network (WBAN) is reported in this letter. The directional antenna is designed using a monopole backed with an electromagnetic bandgap (EBG) structure, which acts as a reflector. The beveled Y-shaped monopole antenna covers the ultrawide bandwidth from 3.1 to 10.6 GHz. The monopole antenna backed with a fork-slotted EBG is designed with a size of 8 × 8 mm2. The 2 × 1 EBG array is printed on the same plane above the partial ground. This integrated structure provides band-stop characteristics from 3.1 to 10.6 GHz with a directional radiation pattern intended for wearable applications. It also acts as a protective shield against the electromagnetic radiation emerging from the monopole antenna toward the body tissue. The proposed directional antenna provides a peak gain of 6.25 dBi with high radiation and total efficiency. The calculated specific absorption rate value is 0.695 W/Kg, which is well below the desired 1.6 W/kg.