Complexity reduced lattice filters for digital speech processing

Several lattice forms and algorithms which constitute the immittance domain alternatives to the PARCOR lattice algorithm are presented. The immittance variables were shown to offer more efficient Levinson algorithms than the conventional scattering algorithms for both symmetric and Hermitian Toeplitz matrices. This paper presents the lattices associated with the new recursions and provides algorithms to determine their coefficients directly from the signal segments. The new lattices are of interest for speech processing as they offer a different parametrization and process real signal segments with only one multiplier and two adders per section. Complex signal segments require two multipliers and adders per section. Stability conditions for the new parametrizations are also presented.