Optimum Design of the Power Dividers with Ferrite Toroids for CATV and/or MATV Systems

The frequency characteristics for the power dividers with ferrite toroids, which are extensively used in CATV and/or MATV systems, are analyzed. The analytical optimum design method for the weakly-coupled power divider by the simplified model and the numerical optimum design method for the tightly-coupled power divider by the exact model are proposed, and the designed power dividers with ferrite toroids by the proposed methods have much improved frequency characteristics compared with the original power dividers. Thus, the useful bandwiths of all the power dividers have been extended from 5 to 500 MHz. Practical measurements show very good agreements with theoretical results, and, hence, the validity of the analyses and design methods for the power dividers with ferrite toroids are confirmed. Furthermore, the relations between the optimum circuit and ferrite constants have been clarified in reference to L0(i)Kfm.