Euclidean Algorithm for Extension of Symmetric Laurent Polynomial Matrix and Its Application in Construction of Multiband Symmetric Perfect Reconstruction Filter Bank

For a given pair of s-dimensional real Laurent polynomials (~a(z),~b(z)), which has a certain type of symmetry and satisfies the dual condition~b(z) T ~a(z) = 1, an s× s Laurent polynomial matrix A(z) (together with its inverse A−1(z)) is called a symmetric Laurent polynomial matrix extension of the dual pair (~a(z),~b(z)) if A(z) has similar symmetry, the inverse A−1(Z) also is a Laurent polynomial matrix, the first column of A(z) is ~a(z) and the first row of A−1(z) is (~b(z))T . In this paper, we introduce the Euclidean symmetric division and the symmetric elementary matrices in the Laurent polynomial ring and reveal their relation. Based on the Euclidean symmetric division algorithm in the Laurent polynomial ring, we develop a novel and effective algorithm for symmetric Laurent polynomial matrix extension. We also apply the algorithm in the construction of multi-band symmetric perfect reconstruction filter banks.