Identification and classification of transient pulses observed in magnetometer array data

Identification and classification of transient pulses observed in magnetometer array data by time-domain principal component analysis filtering

Karl N.Kappler;Daniel D.Schneider;Laura S.MacLean;Thomas E.Bleier

【期刊名称】《地震学报（英文版）》 【年(卷),期】2017(030)004

【摘要】A method for identification of pulsations in time series of magnetic field data which are simultaneously present in multiple channels of data at one or more sensor locations is described.Candidate pulsations of interest are first identified in geomagnetic time series by inspection.Time series of these \events\are represented in matrix form and transpose-multiplied to generate time-domain covariance matrices.The ranked eigenvectors of this matrix are stored as a feature of the pulsation.In the second stage of the algorithm,a sliding window (approximately the width of the training event) is moved across the vector-valued time-series comprising the channels on which the training event was observed.At each window position,the data covariance matrix and associated eigenvectors are calculated.We compare the orientation of the dominant eigenvectors of the training data to those from the windowed data and flag windows where the dominant eigenvectors directions are similar.This was successful in automatically identifying pulses which share polarization and appear to