A novel design of reconfigurable small monopole antenna with switchable band notch and multi‐resonance functions for UWB applications

A novel reconfigurable square monopole antenna with switchable band-notch and multiresonance performances is designed and manufactured.In the proposed structure, by cutting an inverted Γ-shaped slit with variable dimension on the ground plane, new additional resonance is excited and hence much wider impedance bandwidth can be produced, especially at the higher band. Additionally, to generate multiresonance characteristics, we use an inverted U-ring shaped slot, in the ground plane. To achieve reconfigurable function, we use a pin diode across the inverted U-ring slot in the ground plane. When this pin diode is biased, the inverted U-ring slot has converted to a rectangular slot with an E-shaped strip protruded inside the slot, and also by creating this new structure, band notched performance is generated. The designed antenna has a small size of 12 × 18 mm2 while showing the radiation performance in the frequency band of 3.02 to over 12.97 GHz with a band rejection performance in the frequency band of 5.03–5.98 GHz. Simulated and experimental results obtained for this antenna with a reconfigurable frequency function in the range of 5 GHz–6 GHz show that it exhibits good radiation behavior within the UWB frequency range. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:652–656, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27376