Identification of two-dimensional systems using sum-of-cumulants

The use of a sum-of-cumulants as data instead of cumulants is proposed for reducing the computational complexity of two-dimensional cumulant-based identification procedures. The sum-of-cumulants are the Fourier coefficients of a frequency slice of the bispectrum. The dimensionality is thus reduced from four to two without loss of information about the system, and the identification is converted into a rational approximation problem. Non-separable asymmetric half-plane support two-dimensional systems represented by autoregressive moving average (ARMA) models are considered. Determining the region of support of a function of the frequency slice of the bispectrum, the authors obtain, a set of equations for the AR parameters. Cepstral procedures are then used to calculate the MA parameters. The procedure is illustrated by means of examples