Inversion of singular 2-D linear systems (Q1197588)

This paper deals mainly with methods of finding an inverse system for a given singular 2-D linear system. It begins with careful definitions of inverse system and regular system for a singular 2-D linear systems. It then shows that the inverse system of a regular, singular 2-D linear system with transfer matrix of full row rank can be obtained by the use of the realization theory method. It also shows that by applying the singular system structure algorithm, the inverse system of a non-regular singular 2-D linear system can be found by an explicit procedure provided that a nonzero matrix condition is satisfied. In general case each of the presented approaches may give a whole class of inverse systems. Two numerical examples are given, one for regular system and the other for non-regular system. The same symbol ``T'' is used in the paper for transpose of a matrix, a transfer function of the system and a nonsingular transformation matrix. This may cause slight confusion. Other than that, the paper is very well presented!