Serre's Reduction and the Smith Forms of Multivariate Polynomial Matrices

The equivalence of systems plays a critical role in multidimensional systems, which are usually represented by the multivariate polynomial matrices. The Smith form of a matrix is one of the important research contents in polynomial matrices. This paper mainly investigates the Smith forms of some multivariate polynomial matrices. We have obtained several new results and criteria on the reduction of a given multivariate polynomial matrix to its Smith form. These criteria are easily checked by computing the minors of lower order of the given matrix.