Tangent-phase continued-fraction expansion for stable reduced models of linear discrete-time systems

The tangent-phase continued-fraction expansion for stable reduced models is based on the tangent-phase frequency response to the expansion and the factorization technique to obtain reduced models. In this paper, we propose a new procedure for deriving stable and minimum-phase reduced z-transfer functions by the tangent-phase continued-fraction expansion. The procedure is based on transforming the z-domain tangent-phase function to the p domain, where p = z + z^?1?2, and then expanding the p-domain tangent-phase function into a modified continued fraction. An example is given to illustrate the utility of the procedure.