Research On Wideband Omnidirectional Antenna

This paper focuses on the horizontal polarization of the omnidirectional antenna.This paper introduces the research background and significance of broadband omnidirectional antenna,and introduces the development course,characteristics and research trends of broadband omnidirectional antenna.Then,the basic theory of several kinds of polarized omni-directional antennas is discussed in detail,and the radiation performance and physical size of these omni-directional antennas are analyzed and compared.Secondly,this paper studies the radiation principle and performance of horizontally polarized ortho bat wing antenna.The impedance of the designed bat wing antenna is less than 2,the impedance bandwidth is about 60%,the antenna is less than 1.5d B in the whole operating frequency band,and the minimum gain of the antenna is above 1.5d B.In order to further reduce the roundness of the antenna and the size of the antenna to do an innovative improvement study.The improved antenna is not rounded and the size is improved,the roundness is reduced to below 1d B,the size of the antenna compared to the previous improvement is further reduced.The improved bat wing antenna has good omni-directional radiation characteristics and wideband characteristics.Finally,based on the broadband characteristics of vivaldi antenna,an omnidirectional antenna is formed by using vivaldi antenna as array element.This form of omnidirectional antenna using eight vivaldi antenna elements connected to each other to form a circular ring,the feeder network integration design.The characteristics of impedance and pattern are analyzed by simulation.The impedance bandwidth of the antenna is further widened by opening the symmetrical groove of the antenna metal patch.The design of the omni-directional antenna impedance bandwidth of 78%,not roundness within 3d B.