Computation of a canonical form for neutral delay-differential systems

In this paper, symbolic computation techniques are used to obtain a canonical form for polynomial matrices arising from linear delay-differential systems of the neutral type. The canonical form can be regarded as an extension of the companion form, often encountered in the theory of linear systems, described by ordinary differential equations. Using the Smith normal form, the exact connection between the original polynomial matrix and the reduced canonical form is set out. An example is given to illustrate the computational aspects involved.