Realization Theory for Deterministic Boundary-value Descriptor Systems

This paper examines the realization of acausal weighting patterns with two-point boundary-value descriptor systems (TPBVDSs). We restrict our attention to the subclass of TPBVDSs which are extendible, i.e., whose input-output weighting pattern can be extended outwards indefinitely, and stationary, so that their weighting pattern is shift-invariant. Then, given an infinite acausal shift-invariant weighting pattern, the realization problem consists in constructing a minimal TPBVDS over a fixed interval, whose extended weighting pattern matches the given pattern. The realization method which is proposed relies on a new transform, the (s,t) transform, which is used to determine the dimension of a minimal realization, and to construct a minimal realization by factoring two homogeneous rational matrices in the variables s and t.