In this paper, the indepth study of ultrawide band antenna design has been carried out,and the design method of a suitable antenna characteristics is proposed.The proposed antenna design is the comprehensive characteristics of ultrawide band antenna,and is largely based on the frequency domain transfer function to measure the parameters,namely the waveform correlation,waveform broad band draw ratio, waveform relative gain.The simulation results show that the overall performance and characteristics of the antenna performance are very good, especially the antenna aperture has better performance.Through the measurement of these parameters can quantitatively describe the ultra broad band transmission performance.