信号的平稳性检验在信号处理中起着十分重要的作用。介绍Matlab环境下设计和实现信号平稳性检验系统。该系统主要利用替代数据的平稳性特点,通过在时频域中分别计算原数据和对应替代数据的平稳度并相互比较,以实现对信号平稳性的检验。它可以求出输入数据的替代数据,并分析原始数据和替代数据的频域和时频域性质,同时还可以通过计算原始数据和替代数据各自时频域的变化程度来判断原始数据的平稳性。该系统提供了友好的用户界面。实验表明,该系统可方便地完成信号的平稳性检验,对于测试数据给出了较好的检验结果。
Stationarity test remains a challenge problem jn the field of signal processing. Due to the importance of stationarity test,to find a solution to that problem is greatly desired. A stationarity test system designed and implemented based on Matlab is introduced. The system realizes stationarity test via comparing characteristics of original data and surrogate in time - frequency distribution which represent their stationarity. And the comparison on the basis of stationarization property of surrogate which is first explored in time - frequency perspective. The system can make surrogates from original data and display their characteristics in both frequency domain and time - frequency domain. The system can also compare original data with its surrogates in time - frequency domain to determine whether it is stationary or non - stationary. The system gives a friendly interface and is convenient to use. The experiment indicates our system can test stationarity of signal well.