Elliptical UWB Antenna loaded with Rectangular Split Loop Resonator (RSLR) and Semi-Elliptical Slot for Multi band Rejection

This paper presents a compact elliptical monopole Ultrawideband (UWB) antenna, loaded with Rectangular Split loop resonator (RSLR) and Semi - elliptical slot for multi band rejection. RSLR (high Q structures) are introduced for rejection of fixed wireless communication band i.e. 4.5 - 4.9 GHz and Lower WLAN band i.e, 5.1 - 5.3 GHz. For rejecting Upper WLAN band i.e. 5.725 - 5.825 GHz, a semi - elliptical slot is introduced in the radiator. The Ellipticity ratio of the radiator is optimized for achieving a lower cutoff of 3.65 GHz for UWB band, such that WIMAX band is also rejected. The proposed structure is fabricated on 28 x 18 mm(2) RT Duriod 5880 substrate with epsilon(r) = 2.2 and thickness = 0.787mm. Measured VSWR of less than 2 for complete UWB band (except for noteh bandwidths) and constant gain with stable radiation pattern predicts that proposed antenna can be utilized for UWB applications.