双谱估计在地震前兆数字化资料分析中的应用  

Application of Bispectrum Estimation in Digital Earthquake Precursory Monitoring Data

作　　者：刘希强[1] 周彦文[1] 李红[1] 王梅[1] 石玉燕[1] 张坤[1] 

机构地区：[1]山东省地震局,山东济南250014

出　　处：《西北地震学报》2007年第3期201-206,212,共7页Northwestern Seismological Journal

基　　金：国家"十五"地震科技攻关项目(2004BA601B01-03-02);山东省自然科学基金(Y2000E08)

摘　　要：仿真信号的试验结果表明,基于双谱的时延估计方法对高斯噪声具有屏蔽能力,能更好地压制噪声,并准确估计信号的时间延迟;基于双谱功率谱重构要比直接用FFT变换方法估计功率谱具有更高的精度和性能;初步研究结果表明,对于正常背景下的前兆观测记录基于双谱的特征参数分布具有较好的一致性,在异常背景下则表现出明显的离散性,显现出双谱估计具有良好的异常信息识别能力。The test results for emulative signal indicate that the time delay estimation method Of bispectrum has the capacity to suppress Gauss noise and can accurately estimate the time delay of signals. Compared with Fourier transform method, the spectrum power reconstruction method of bispectrum has higher accuracy and capability. The research results show that the characteristic parameter distribution of bispectrum has a good consistent characteristics to the normal earthquake precursory monitoring data, but has a obvious dispersion characteristics to the abnormal data, which indicats that bispectrum has the discrimination capability to earthquake precursory anomalies in monitoring data.

关 键 词：双谱理论 时延估计 功率谱重构 双谱特征参数 地震前兆异常识别 

分 类 号：P315.61[天文地球—地震学]