Base On Fractal Structure Of UWB Antennas' Research And Simulations

System of Ultra-Wideband (UWB) telecommunication is the one that adopts extremely short pulse in time doman which occupies large frequency band. To satisfy the demand of undistorded transmission, the antenna should have several or more octave impedance bandwidth and stable phase center. It's presented in this dissertaoin that design and simulation on UWB antenna based on fractal and microstrip theory.First, it's introduced that state of the art of the ultra-wideband antenna and the definitions of several performance parameters. Some further theoretical analysis on UWB antenna radiation characteristic property is also outlined.Second, it's introduced several antenna methods of MoM, FEM, FIT and their performance comparison. Analysis of FIT is discussed in detail and an electromagnetic simulated software CST which based on FIT is briefly introcuded.Third, it's investigated that design method of UWB antenna which is based on fractal theory and its potencial in application is also analysed and demonstrated.At last, in order to meet the ultra-wideband system demands, two microstrip antenna improvement designs are given on the basis of traditional antenna and fractal theory. The simulation results showed that the improved antenna has ultra-wideband and stationary phase center which statisfies the need of UWB telecommunication.