Design of a rectangular UWB slot antenna dual-band notched at 3.5/5.7 GHz

Abstract

Recently, ultra wideband (UWB) communication systems have been developed widely and rapidly, which lead to a great demand in designing wideband microwave components, such as antennas, and filters. Several antenna configurations including planar monopoles and dipoles have been studied and proposed for ultra broadband applications; however the use of the 3.5 GHz and 5.7 GHz band is reserved for the WiMAX band and High Performance Local Area Network (HiPerLAN) band, respectively. Therefore, a band-rejection filter is necessary in UWB RF front-ends, and this will provide insertion-loss problem, pattern radiation stability, and more complications for UWB systems. Accordingly, and in order to resolve this problem, some works to notch the HiPerLAN (WLAN) and (or) WiMAX bands have been reported and widely discussed [2]-[5]. Planar antennas are suitable solutions to achieve low-cost and reliable radiating device for UWB systems. To overcome these problems, several works have been achieved in this area. A common approach is to use UWB monopole antenna with different shapes [3]. Other techniques with notch function have also been investigated such as such as, the insertion of the split ring slot resonator, the U-shaped slot resonant structure, or stubs [4–5]. Lee et al. [6] have proposed to perturb matching impedance and create an open circuit at the undesired band. However, these techniques can eliminate only one band, or cannot provide a sufficient rejection bandwidth to be used in practical applications. Some others UWB antenna designs use filters to suppress undesirable bands, but the uses of filters increase the complexity of the UWB systems, and consequently their cost [7].