Minimization of the Size of an Antipodal Vivaldi Antenna for Wi-MAX and WLAN Applications

In this paper, miniaturization of the antipodal Vivaldi antenna is discussed. The antipodal Vivaldi antenna is a broadband antenna and thus it is suitable for use in many wireless applications. The proposed antenna has a center frequency at 3.6, 5.2, and 5.8 GHz and so it can be used in WiMAX as well as WLAN systems and to avoid potential interference from narrowband communication systems, it is advised to design a miniaturized broadband antenna with intrinsic band-notched characteristics which can be used in narrowband communication. The circular slots are applied on the edge at the width of the Vivaldi antenna and are etched properly and as a result this helps in the area minimization of the antenna. The circular slot with the greatest diameter is used to achieve the different center frequencies so that the proposed antenna can be used for wireless communication, i.e. for WiMAX and WLAN. The rectangles are used on the alternative circular slots so as it can be used as notched structure and the interference in between the two different wireless applications can be minimized. The bandwidth of the proposed antenna is 2.8-6.2 GHz. A comparison of a conventional Vivaldi antenna with an antipodal antenna is also undertaken. The simulation of the proposed antenna was performed using HFSS13.0 software. The return loss, gain, radiation pattern, z-parameters, and VSWR are shown.