High-order spectra of mixture processes

Summary form only given. In certain processes higher-order spectra reveal more information than second-order spectra. For example, the bispectrum has been applied to determine deviations from Gaussianness, to determine phase information in nonGaussian linear processes, and in nonlinear interactions. The trispectrum has also been used to extract phase information from nonGaussian signals. For the present study, the application is to determine whether or not a nonGaussian process is present from its higher-order spectrum. Initially, a nonGaussian process is modeled as a parameterized mixture process. Then the theoretical spectra and higher-order spectra are derived based on the mixture process. Simulations are shown of the measured spectra and higher-order spectra from mixture processes. The results are pertinent to the modeling of underwater acoustic signals.<>