Design And Optimization Of Bi Coni Cal Antennas

Biconical antenna is one of the most representative ultrawideband(UWB)antennas.It has attracted great attention because of its advantages,such as wide frequency band,high gain,good directional property within operating bandwidth.Biconical antenna has been widely used in satellite communication,radar system,radio monitoring system,electromagnetic compatibility test,and so on.This paper summarized the development history and research status of biconical antenna,and three kinds of biconical antennas were designed and optimized,specifically carried out the following works:Firstly,the theory of biconical antenna was introduced briefly.Then a symmetrical biconical antenna was simulated with ANSOFT HFSS 15.0.It has the operating frequency range from 3.1 GHz to 10.6 GHz,in whole frequency band,the voltage standing wave ratio(VPWRS)is less than 2,and the return loss(S11)is less than-10dB.It can meet the basic requirements of communication system for antenna.Next,the asymmetric biconical antennas were briefly classified.On the basis of the symmetric biconical antenna,four important parameters which affect the performance of the biconical antenna were discussed,that is to say,changed the four important parameters separately,established corresponding models and simulate calculated,analyzed results by the experimental data.After several experiments,as a result,a asymmetric biconical antenna of more excellent comprehensive properties was obtained.The operating frequency is 3.1 GHz-10.6GHz,the voltage standing wave ratio(YWRS)is less than 1.8,the return loss(S11)is less than-11dB,and the comprehensive performance is better than the symmetrical structure.A biconical antenna with magnetic dipole was simulated by ANSOFT HFSS 15.0.The operating frequency band is 200 MHz-985 MHz.Obviously,the magnetic dipole has a good improvement effect on the voltage standing wave ratio(VWVRS and the return loss(S11)of the biconical antenna.Based on the result above,loaded the magnetic dipole circuit on the asymmetric biconical antenna structure,and an electromagnetic biconical antenna with better performance was obtained.The voltage standing wave ratio(VWRS)and the return loss(S11 have been improved greatly,and the voltage standing wave ratio(VWRS)is less than 1.5,the return loss(S11)is less than-14dB from 3.1 GHz to 10.6 GHz,and it has a good direction performance.The biconical antenna array was simulated.Firstly,the appropriate half-cone angle was selected,the generatrix range of the biconical antenna was estimated by empirical formula,the model was established and simulated with ANSOFT HFSS 15.0,so the array element was obtained.The gain characteristics and directional performance were mainly investigated,and the element was optimized several times,and the biconical antenna with coverage frequency from 960 MHz to 1215 MHz was obtained.Finally,the elements were formed into different line arrays,so that biconical antenna arrays with stronger gain and better directional performance were acquired.