A continuously-adaptive filter implemented as a lattice structure

This paper is concerned with the use of adaptive, linear, non-recursive digital filters. Filters of this type are generally implemented in tapped-delay-line form and have been widely used in linear prediction filtering, spectral estimation and noise cancelling applications. Recently, an alternative implementation, called the lattice structure, has been proposed for fixed-coefficient recursive and non-recursive digital filters. The purpose of this paper is to present a class of adaptive algorithms suitable for use with the lattice structure, and to compare these algorithms with the conventional tapped-delay-line implementation. It is suggested that the successive orthogonalization offered by the lattice may provide convergence advantages not obtainable with tapped-delay-line methods.