Refined ARMA digital lattice filter

This paper introduces a new ARMA digital lattice filter. It can be designed from the recursive formulae which solve estimation error filter equations for an ARMA model. This filter consists of two elementary sections. These sections are an AR type elementary section which realizes the AR part of the estimated ARMA model, and an MA type elementary section which realizes the MA part of the estimated ARMA model. By using these sections, we can design the ARMA digital lattice filter with an arbitrary AR and an arbitrary MA order, and easily test its stability. In addition, some experimental results for a real speech waveform are shown.