Patent ID: 6617941
Filing Date: 2003-09-09
Classification: H03H

Abstract:
A method for designing a filter system withat least two longitudinal branches having longitudinal inductors, at least one filter section, which has at least one transverse branch interposed between the longitudinal branches, and at least one adjacent filter section, which adjoins the transverse branch, wherein the configuration of the inductors is determined by means of transformation by the following process steps: first, the filter section has at least one free longitudinal inductor of the first longitudinal branch, a free longitudinal inductor of the second longitudinal branch coupled therewith and the transverse branch, which consists of a capacitor that is interposed between two transverse inductors coupled with each other, and first the adjacent filter section has at least one free longitudinal inductor of the first longitudinal branch and a free longitudinal inductor of the second longitudinal branch coupled therewith, subsequently, in each longitudinal branch between the transverse branch and the adjacent filter section a preliminary longitudinal inductor and a compensating inductor compensating the same and connected in series therewith are inserted, wherein the preliminary longitudinal inductors are coupled with each other and the compensation inductors are coupled with each other, subsequently, the compensation inductors are integrated into the free longitudinal inductors of the adjacent filter step, subsequently, the preliminary longitudinal inductors, the free longitudinal inductors of the filter section and the transverse inductors are replaced by four end inductors that are coupled with each other such that an equivalent circuit diagram of the four end inductors corresponds with the circuit diagram of the preliminary longitudinal inductors, the free longitudinal inductors of the filter section and the transverse inductors.