Blind separation of three-component seismic signal with the higher-order statistics

利用高阶统计量盲分离三分量地震信号

• 批准号: 13650980
• 负责人: NAGANO Koji
• 金额: $ 0.64万
• 依托单位: MURORAN INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650980/
• 关键词: Independent component analysis; Blind separation; Seismic waves; Subsurface instrumentation; Geothermal energy; ブラインドセパレーション; 地熱開発

Duration of an elliptically polarized wave is detected by using the blind signal separation and the cross-correlation analysis in three-component seismic signals. Observed three-component signals are assumed to be linear combinations of the elliptically polarized wave and another wave. The fourth-order cumulant, kurtosis, is used to measure a degree of the independence of the transformed signals. To actually minimize or maximize the kurtosis, a fixed-point algorithm is employed. Duration of the polarized wave is detected by analyzing the cross-correlation functions between the half of pi phase-shifted signal and the zero phase-shifted signal. The duration of crack-waves which have the elliptical particle motion is detected well by using the algorithm. Analytic signal transformed from the observed signal is also used in the blind separation. The algorithm using the analytic signal decreases ambiguity of a result.A function based on the normalized fourth order cumulant, kurtosis, is used to detect the P-wave arrival time. Errors of the automatic detection are within 6 ms in 87 acoustic emission signals.

利用盲信号分离和互相关分析方法，对三分量地震信号中椭圆偏振波的持续时间进行了检测。观测到的三分量信号被假定为椭圆偏振波和另一波的线性组合。四阶累积量，峰度，被用来衡量变换后的信号的独立程度。为了实际最小化或最大化峰度，采用固定点算法。通过分析π相移信号的一半与零相移信号之间的互相关函数来检测偏振波的持续时间。该算法较好地检测了质点运动为椭圆形的裂纹波的持续时间。从观测信号转换的解析信号也被用于盲分离。该算法利用解析信号减少了结果的模糊性，并利用归一化四阶累积量的峰度函数检测P波到时。87个声发射信号的自动检测误差在6ms以内。