Frequency Reconfigurable Antenna Inspired by Metamaterial for WLAN and WiMAX Application Shashanka Sekhar Behera 1 ,Sudhakar Sahu 2 School Of Electronics Engineering, KIIT University shashanka1988@gmail.com 1 , ssahufet@kiit.ac.in Abstract— A frequency reconfigurable antenna inspired by metamaterial for WLAN and WiMAX application was presented. Two different antenna was proposed namely antenna (1) & antenna (2). Antenna (1) is designed to resonates at 5.2 GHz(WLAN Band) with impedance bandwidth 1.4407 GHz. The Antenna (2) is the extension of antenna (1). Two resonating particles in antenna (2) excited by dynamic magnetic field which produces negative permeability due to coupling with the monopole antenna; the whole structure is now a tri-band antenna. The antenna (2) sometimes produces tri-band resonates at 3.5 GHz (middle WiMAX) & 5.56 GHz(Upper WiMAX band), 4.65 GHz having overall bandwidth 1.9356 GHz, sometimes produces dual bands 3.5GHz and 5.3 GHz(WiMAX and WLAN band) having overall bandwidth 1.6445GHz, sometimes at single band 5.15GHz (WLAN band) having impedance bandwidth 1.4917 GHz .By introducing a single switch at each metamaterial cell, their effect can be deactivated and their corresponding resonance can be eliminated, and that results a frequency reconfigurable antenna. The job of unit omega cell only to shift center frequency of monopole 5.2GHz(WLAN band) to 5.56 GHz(Upper WiMAX band application).All structures had simulated using Finite Element Method(FEM) based on HFSS. Index Terms— DSRR, FEM, HFSS, omega, metamaterial SRR. I. INTRODUCTION The growing demand of wireless communication forced researchers to design antenna which operates at multiband frequency to support MIMO. MIMO is preferred as signal fading minimized and capacity can be improved. This is particularly essential for cognitive radios (CRs) where a broadband antenna sense to larger band and the narrowband antenna could change the operating frequency band when needed[1, 2]. So the modern radios are having multi frequency operation tendency but it increased the complexity of the hardware part both at front end and at the decoder unit. Now a days researchers are interested in complexity in antenna level, Which supports filtering at antenna level. For which it can reduce filtering in digital part which save space. Examples of antennas with integrated filtering capabilities can be found in [3, 4]. In these examples, the antennas are wideband and the filtering consists in suppressing parts of the operating frequency band. Another approach that can be used consists in using multiband antennas with the capability of suppressing either of the bands [5, 6]. The proposed antenna is a multiband one with frequency reconfiguration capability based on metamaterial properties. To achieve multiband behavior, negative-permeability cells are used in conjunction with a monopole to create new resonances[7]. To achieve frequency reconfiguration, a switch is integrated to each cell in order to activate or deactivate them[8]. The on/off states of the switches are modeled by the presence/absence of a perfect conductor. The Ansys High Frequency Structure Simulator(HFSS) version 14[9] was used for modeling and analysis of the two proposed antenna . In section II geometry of the proposed antennas are presented. Their reflection coefficient radiation pattern and gain are discussed in section III. Finally section IV concludes the major finding of those two antennas. (a) (b) Fig. 1 Presentation of the proposed antenna (1) (a) Top View (b Bottom view 20 mm 3 mm 38 mm 34 mm 24.4 mm 10 mm 442 978-1-4799-3140-8/14/$31.00 c 2014 IEEE