Design and Analysis of Reconfigurable Microstrip Antenna for Cognitive Radio Applications

A compact and reconfigurable band notch UWB antenna for cognitive radio application has been proposed in this paper. The proposed UWB antenna has dual notch band in WI-max and WLAN and has reconfigurable property in terms of band notching for a single notch band in Wi-Max. Reconfigurable property of the presented antenna in WLAN band has been achieved by using a MEMS switches. The ON and OFF conditions of the MEMS switch are actually responsible to achieve the reconfigurable property. The proposed two notch bands (WI-max and WLAN) are obtained by embedding an elliptical slot on radiating patch and a rectangular strip on ground plane respectively. Empirical relations related to the proposed design for elliptical slots to obtain desired notch band have also been included in this paper. The impacts of the design parameters on notch characteristics of the antenna have also investigated. The design and functional simulation of the proposed antenna structure have performed by using HFSS-v14. A fully functional prototype has fabricated and measured and the measured results have shown a good agreement with the simulations.