Realization of Minimum-Phase and Nonminimum-Phase Transfer Functions by RLC Ladder-Type Networks

A conceptual framework is erected which will give better control, it is hoped, to the designer of unbalanced RLC networks that are to realize prescribed, minimum-phase or nonminimum-phase transfer functions. Maneuverability is achieved by introducing a set of "elementary sections," which are constructed from the individual factors of the prescribed transfer function. The rules for the interconnection of these sections are derived from an equivalent-network scheme which contains "generalized, ideal transformers," but mutual inductance is absent altogether from the synthesized networks. The majority of design deliberations can take place in terms of network concepts discussed in Sections II-IV, while the role of purely formal, algebraic manipulations is intentionally minimized. Four different illustrative designs, which realize new networks for transfer functions previously used by E. C. Ho and L. Weinberg, are carried out step by step. In each of the four cases the network designed in Section V of this paper exhibits substantial improvements. The approach chosen in this paper is put into perspective with regard to pertinent synthesis papers by E. C. Ho, G. L. Matthaei, R. H. Pantell, and L. Weinberg, and the equalizer design techniques of O. Zobel and H. W. Bode. This makes it necessary also to examine the relationship between some of these papers, which is done primarily in Appendix I.