Compact Tapered Fed Dual-Band Monopole Antenna for WLAN and WiMAX Application

In this paper a compact tapered fed dual band monopole antenna based on complimentary split ring resonators(CSRR) used for WLAN and WiMAX application. Two CSRR are placed side by side symmetrically, which produces a narrow stop band in a single band for which dual band observed. As over all bandwidth reduces the gain is improved. The composite metamaterial CSRR can provide dual band operation at 1.9-2.6 and 2.92-4.3 GHz with reflection coefficient less than-10 dB by the two resonant modes due to CSRR and length of the patch. The gain at lower resonant band -2-0.2 dB and at higher resonant band 0.5-2 dB. A 50 LI microstrip line, followed by parabolic feed and rectangle step feed is adopted for impedance matching. The uniqueness of this design is that the CSRR generates a narrow stop band in a wideband produced by an element without having any CSRR, which makes the dual band antenna very compact. Antenna parameters like reflection coefficient, radiation pattern, gain are analyzed with numerical simulation.