Abstract-This paper proposes a novel, low-profile UWB antenna for wireless body area network (WBAN) applications. The antenna has a polarization perpendicular to the body-free-space interface, which is interesting in order to minimize the coupling into the body. Its structure comprises a modified mono-cone with a top-cross-plate and is coaxially fed through the ground plane. The higher frequency band performance is due to the mono-cone while the top-cross-plate is responsible for the lower frequency band. This plate also leads to a height reduction when compared to conventional mono-cone antennas. A comprehensive parametric study is done to provide design guidelines. Both frequency-and time-domain results have been measured and presented to validate the design. Results show that the antenna operates from 3.06 to beyond 12 GHz based on dB, radiates omni-directionally in the -plane, and has a radiation efficiency over 95%. The system-fidelity factor for UWB signals is adequate for pulse transmission. Finally, the influence of the human proximity on the antenna matching was tested. Results show that its impedance is nearly unchanged as compared to free-space.Index Terms-Frequency-and time-domain, low profile, UWB antenna, vertically polarized, wireless body area network.

No abstract

No abstract

Abstract-This letter studies the frequency-and time-domain performance of a recently developed printed coplanar-fed ultrawideband (UWB) monopole antenna aiming at predicting its behavior close to a human arm. The input reflection coefficient and fidelity factor of the antenna were evaluated in free space and close to an arm. Simulations using three simplified arm models with different cross sections (flat, rectangular, and elliptical) were compared to measurements. All models include the relevant human tissue layers: skin, fat, muscle, and bone. It was found that an accurate model requires the inclusion of the tissues broadband dispersion characterization. Moreover, the skin layer has a major impact in , and a small effect on fidelity, while the models can be simplified by discarding the bone. Furthermore, the geometry of the models is less relevant than dispersion characterization. It has also been observed that using the simplified models with proper broadband tissues dispersion yields good performance predictions, and that the fidelity factor increases as the antenna gets closer to the arm.Index Terms-Fidelity factor, frequency and time domain, frequency-dependent materials, human body effects, ultrawideband (UWB) antenna.