SYNTHESIS OF ARMA FILTERS BY REAL LOSSLESS DIGITAL LATTICES

A new method is presented to obtain degree-one or real degree-two tran sfer scattering matrices of two-port lossless lattice filters through the use of complex Richard's function extractions for the minimum degr ee cascade synthesis of real, stable, single-input, single-output ARMA (n, m) filters from the transfer function or the input reflection coe fficient, The method relies on a four-step Richard's function extracti on where two steps are used for reducing the degree of the transfer fu nction and two for obtaining real lattices, We treat the cases where t he zeros of transmission are inside and outside the unit circle but no t on the unit circle.