提出了基于Wigner分布(WD)的判定混沌信号的改进方法。利用混沌信号的窄带特性和三维时频谱图的峰值波动情况判定混沌信号。该方法经洛伦兹系统验证是可行的。计算了混沌信号与高斯噪声的Wigner分布, 结果表明可以从三维时频谱直接将两者区分开。计算基于半导体光放大器(SOA)的环形激光器输出光实验数据的三维时频谱, 结果与洛伦兹系统的非常相似, 从而可判定该实验装置产生信号确为混沌信号。Wigner分布三维时频谱准确地反映了信号的谱特性, 能够将系统的不稳状态与混沌状态以及噪声区分开。无论是由动力学方程产生的混沌还是实验上产生的混沌信号都可直观、有效地进行判定。

An improved method of distinguishing chaotic signal based on Wigner distribution (WD) is presented. The narrow band characteristic and the peak value fluctuation of the three-dimensional time-frequency spectrum are used to distinguish chaotic signal. The method is proved to be feasible by the calculation of Lorentz system. The WD of the chaotic signal is compared with that of the Gaussian noise, and the result indicated that their spectra can be distinguished. The WD is used to dispose the output light of the fiber ring laser base on semiconductor optical amplifier (SOA) too, and the result is similar to that of Lorentz system. So it could be verified that the experiment output is chaotic light. Three-dimensional WD accurately shows the spectral characteristic of the signal and can be used to differentiate whether the system is in nonstable state or chaotic state or noise. It is an intuitive and effective method for distinguishing the chaos either generated from dynamic equations or experiment output.