NORMAL-MODE ANALYSIS OF FERRITE-COUPLED LINES USING MICROSTRIPS OR SLOTLINES

A normal-mode analysis of a pair of axially-magnetized ferrite-coupled lines (FCL) is presented for the first time, This normal-mode method, as opposed to the coupled-mode method, will permit optimization of pr opagation characteristics and impedance-matching. Also, the finite ele ment solution of the normal modes can be used to obtain the field dist ribution to assist suitable placement of ferrite for device applicatio ns, Potential applications include a novel 4-port distributed microstr ip circulator which may have advantages over junction devices at milli metric wavelengths, Optimum normal-mode conditions for the use of the FCL as a component in the distributed circulator are derived, and the design procedure for microstrip FCL is presented for the first time.