Design and analysis of a ultra-wideband antenna with triple frequency filtering characteristics

This paper aims to design an ultra-wideband (UWB) antenna with triple frequency filtering functions. The proposed antenna is comprised of a circular wide-slot that is etched on CPW ground plane, a radiating patch of circular ring shape, a pair of T-shaped stubs (TSS) and an isolation element (IE) that is horizontally inserted into the circular ring radiating patch, a loaded arc-shaped stub (LAS) connected with the CPW ground plane and a CPW ground plane together with a 50-Ohm CPW feed structure. The triple frequency filtering functions are obtained by using the TSS and LAS. The LAS produces the middle notch band at 5.5 GHz WLAN band, while the TSS is designed to give a lower notch at 3.5 GHz WiMAX band and a higher notch at 7.8 GHz X band. The good performance of the wide bandwidth, triple notched bands and omnidirectional radiation patterns make the proposed antenna a good candidate for indoor UWB utilization.