水下目标辐射噪声的非线性检验

由于非线性是混沌产生的必要条件,所以讨论一个观测时间序列是否具有非线性,对进一步利用混沌时间序列方法分析观测时间序列很有意义。本文讨论水下目标辐射噪声信号中非线性问题,运用替代数据方法,根据实验数据与替代数据之间峭度和自相关两个量的差异性,分析了水下目标辐射噪声信号中的非线性成分,得出结论:水下目标辐射噪声信号中存在非线性成分,且这种非线性不是由于静态测量函数的非线性引起的,为利用非线性时间序列分析方法分析水下目标噪声信号提供了理论依据。

Detecting nonlinearity in the radiated noise of underwater targets

Since non-linearity is a necessary condition for chaotic behavior, the question whether an obserVed time series consist of nonlinear ingredients is of particular interest for the fUrther analysis of the time series with the chaotic approach. This paper discusses non-linearity in the radiated noise from Underwater targets with the surrogate data method. By comparing the differences of a third-order quantity and the third-order auto-correlation between observed data and surrogate data, the non-linearity in the radiated noise is analyzed. The results conclude that there exist non-linearity ingredients in the radiated noise from underwater targets and the non-linearity is not caused by the static nonlinear transformation measurement. The results provide theoretical foundation for the analysis of the radiated noise from underwater targets with the nonlinear time series method.