A new band-notched printed monopole antenna for UWB applications

An ultra-wideband (UWB) U type monopole antenna fed by a coplanar waveguide (CPW) with band-notch characteristic is proposed. Printed on a 0.8 mm thick FR4 substrate with relative permittivity of 4.4, it has low profile and very compact size (14.48mmX28.74mm), only around 0.14 lambda X 0.28 lambda in electrical length (lambda is the wavelength of lower frequency 2.95GHz). It provides an wide impedance bandwidth ranging from 2.95GHz to about 12.65 GHz (124.4%), and presents a notched band from 5.13 to 5.9 GHz for VSWR >= 3, which covers the wireless local area network (WLAN) band. The time-domain behaviors are discussed and the group delay is given. The proposed antenna has a compact size, ultra wide bandwidth, good radiation characteristics, and good time-domain behaviors to satisfy the requirements of the current and future wireless communications systems. Details of the proposed ultra-wideband design are described and parametric study is presented.