UWB antenna using offset feeding and slotted ground plane for on-body communications

An offset-fed Ultra-wideband (UWB) antenna with a slotted ground plane designed for on-body communications is presented in this paper. The antenna consists of a nearly square-shaped radiator, a feed line slightly offset from the middle along the radiator side and a ground plane with several rectangular slots. The offset feed line improves the radiation pattern for on-body communications and the slots on the ground plane improve impedance matching. Simulated and measured results are in good agreement in terms of S11, gain, efficiency and radiation pattern. Measured results show that the antenna can achieve a wide bandwidth from 2.4 to 14.5 GHz, a constant peak gain and high efficiency, and a more omnidirectional radiation pattern in E-plane, making it a good candidate for UWB on-body communications.