高次스펙트럼의 機械的 시스템 適用 硏究,(1) - 바이스펙트럼과 2次 位相結合 解析 -

This paper is concerned with the development of useful engineering techniques to detect and analyse nonlinearities in mechanical systems. The methods developed are based on the concepts of higher order spectra. The study of higher order statistics has been dominated by work on the bispectrum. The bispectrum can be viewed as a decomposition of the third moment(skewness) of a signal over frequency and as such is blind to symmetric nonlinearities. The phenomenon of quadratic phase coupling(QPC) can be analyzed by bicoherence function. Finally. the application of these techniques to data from actual mechanical systems will be performed in second report.