an improved cpw-fed printed uwb antenna with controllable band-notched functions

a newly designed printed slot antenna is presented that incorporates variable two band-notched functions for ultra-wideband (uwb) applications. the two band notches of this coplanar waveguide (cpw) fed antenna are achieved by an m-shaped slot (mss) embedded in the radiating element and a c-shaped strip(css) close to ground plane, therefore two very narrow rejected properties in the wireless local area network (wlan) band (5.15-5.825 ghz) and worldwide interoperability for microwave access (wimax) operation in the (3.3-3.7ghz) are obtained. the rectangular aperture is etched in the square ground plane. it has a determinative role in antenna’s impedance band width (ibw) enhancement, moreover, by adjusting carefully it leads to wide ibw. based on simulated results it covers the frequency range 2.4–12.9 ghz with vswr ≤ 2, which corresponds to a fractional bandwidth of 137% excluding the rejected bands. numerical and experimental results are presented to understand its behavior. the volume of the proposed antenna is 25 × 25 × 0.8 mm3.