Abstract
In this article, we propose the design of a coplanar waveguide (CPW)-fed circular slot antenna, with dual frequency rejection characteristics for ultra-wideband communication applications. The dual frequency rejection function is realized by inserting a stepped impedance stub (SIS) inside the circular ring radiation patch and by using an arc-shaped parasitic element (ASPE) along the circular ring radiation patch. The center frequencies of these rejection bands can be controlled by adjusting the dimensions of the SIS and the ASPE. The antenna has been designed, optimized, and fabricated, and its performance has been verified through measurements, which show that it can operate across a wide bandwidth ranging from 2.7 to 11.6 GHz with a VSWR < 2, and that it provides dual-band rejection characteristics at both the WLAN band and the X-band. (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:783-787, 2014