UWB Monopole Antenna with Dual Band-Stop Performance Using G-Shaped SRR and SIR Structures at Feed Line

This article presents a new design of ultra-wideband monopole antenna with the characteristics of dual band rejection. The antenna consists of a circular radiating patch, a feed-line with G-shaped Step-Impedance Resonator (SIR) slot and Split-Ring Resonator (SRR) structure, and a ground plane which provides a wide usable fractional bandwidth of more than 120% with two notch bands around 5.15-5.35 GHz and 7.25-7.75 GHz, to avoid interferences from High Performance Radio Local Area Networks (HIPERLAN) and downlink frequency of X-band satellite systems. The simulated and measured results show that the antenna design exhibits an operating bandwidth (VSWR<2) from 2.86 to 12.92 GHz, excluding the rejected bands. The proposed antenna configuration is simple, easy to fabricate and can be integrated into any UWB system. The antenna has an ordinary circular-disc radiating patch, therefore displays good omnidirectional radiation patterns, even at higher frequencies.