A new planar ultra wideband antenna for UWB applications

The recent allocation of the 3.1-10.6 GHz frequency spectrums for ultra-wideband (UWB) applications has presented many opportunities and challenges for antenna designers. Patch antennas are extensively used in wireless communications because of their light weight, low cost, and ease of fabrication. These features are desirable for both indoor and outdoor handheld UWB antenna applications. Ideally, UWB antennas should be non-dispersive or dispersive in a controlled fashion that is amenable to compensation. In this paper, to avoid the feeding problems and also costly fabrication, we modified the shape of the elliptical antenna by bending edges and cutting metal sections appropriately. The antenna structural parameters are then optimized to improve its performance. To avoid using the balun transformer and also to improve the antenna dispersion characteristics, the complement structure of the antenna was considered which results in a dragonfly shape antenna. The designed antenna was fabricated and the simulation results have been verified by comparing with measurements.