Higher order statistical analysis of fluctuations in a plasma

Turbulent fluctuations are a common phenomena in most plasma systems. Most of the analysis is done by conventional Fourier techniques that extract information only in the frequency domain with temporal information usually missing. Also non-linear interaction between different modes cannot be identified. We present in this paper some new techniques using wavelet transforms and bispectral analysis that enable interpretation of non-stationary signals and also yield information about non-linear coupling between different basic modes of the system.