This paper is devoted to a study of symmetric paraunitary matrix extensions
. The problem for a given compactly supported orthonormal scaling vector wi
th some symmetric property, to construct a corresponding multiwavelet which
also has the symmetric property, is equivalent to the symmetric paraunitar
y extension of a given matrix. In this paper we study symmetric paraunitary
extensions of two types of matrices which correspond to two different case
s for the symmetry of the scaling vector: the components of the scaling vec
tor hav or don't hav the same symmetric center. In this paper we also discu
ss parametrizations of symmetric orthogonal multifilter banks.