Slice spectra approach to two-dimensional cubic nonlinear phase coupling estimation

For the problem of two-dimensional (2-D) cubic nonlinear phase coupling estimation, special fourth-order cumulant and corresponding slice spectrum of fourth-order cumulant are defined. The slice spectrum of fourth-order cumulant approach is proposed for estimating two-dimensional cubic nonlinear phase coupling. As the fourth-order cumulant of a complex process has 2 different definitions, two definitions are used to extract the coupled and coupling frequency components in Gaussian noise , respectively. Hence the nonlinearity of system is detected effectively. Simulation examples are presented to prove the results of this paper.