Reviews and abstracts - Suboptimal system approximation/identification with known error

Abstract

Abstract : This paper presents a noniterative method for approximating empirical signals over 0, infinity by a linear combination of exponentials. The technique results in a suboptimal approximation. Notably, the dependence of the suboptimal exponents s'sub i on the integral square error epsilon is such that lim epsilon approaches Limit of 0) s'sub i = s sub i, the optimal exponents. The method may also be used for system identification. It is especially useful when the system is modelled by a black box and one has access only to the input and output terminals of the system. A technique is demonstrated to find the multiple poles of a system along with the residues at the poles when the output of the system to a known input is given. Among the advantages of the method are its natural insensitivity to noise in the data and the explicit determination of the signal order. Representative computations are made of the poles from the transient response of a conducting pipe tested at the ATHAMAS-I EMP simulator.