A NEW CONICAL BAND-REJECT UWB ANTENNA WITH UNIFORM REJECTION AND STABLE OMNIDIRECTIONAL BEHAVIOR

This paper introduces a new volumetric conical notch-band antenna. Structure of this antenna is in contrast with planar and printed band rejection antennas currently existing in almost all of the literatures. The radiation pattern of the proposed antenna is symmetrical and stable against frequency variation, while planar and printed antenna types suffer from high variation of their radiation pattern with frequency, and consequently asymmetric and unstable omnidirectional behavior. The frequency band of the antenna is notched with two slots implemented on the antenna structure. Uniform various frequency band rejections are achieved by changing the slots dimensions and position. Both measured and simulation results of manufactured antenna show the frequency bandwidth of the antenna is from 3 to 4.9GHz and from 6.2 to 11GHz with reflection coefficient less than −10 dB. Moreover, the antenna notches the frequency band from 4.9 to 6.2GHz with nearly uniform reflection coefficient level of approximately −3 dB. Stable radiation pattern and proper range of frequency band rejection make the designed antenna an appropriate candidate for the use in UWB and indoor communication systems.