Detection of Weak Simple Harmonic Signal in Strong Noise Based by Use of Chaotic Oscillator

Duffing oscillators response to external simple harmonic excitation was studied by using numerical analysis method. With the increasing of amplitude of the simple harmonic excitation, the behavior of the system changed qualitatively in some critical values of the amplitude, such as from periodic oscillation to chaos. When the excitation was polluted by noises or other harmonic signals whose frequencies were higher or lower enough than the excitations frequency, the critical values changed little. The oscillator could be applied to detect weak simple harmonic signal in the strong noise based on this character. Since primary phase of the simple harmonic component to be detected in the sampled signal was unknown, the method which ignored primary phase didnt work any longer when primary phase was concerned. Phase delay method was introduced to solve the problem. Numerical simulation indicated that simple harmonic signal with Gauss noise could be detected when SNR was bigger than -90dB.
chaotic oscillator Duffing oscillator simple harmonic signal signal detection numerical analysis
Gao HongBin OuYang GuangYao Zhu ShiJian Shao LiMin
Naval University of Engineering,Shipping and Power Academy,Wuhan 430033,China
国际会议
西安
英文
2007-08-16(万方平台首次上网日期,不代表论文的发表时间)