Edinburgh Napier University

  A switchable circulator may be realized by internally or externally switching or latching a suitable ferrite resonator at the junction of three transmission lines or waveguides. This paper investigates the split frequencies and therefore the quality factor of a geometry consisting of a half wave-long cylindrical cavity and another which consists of a tri-toroidal structure. The model adopted in this paper divides the surface of the resonator into up and down uniformly magnetized but unequal regions. The boundary, between the two regions, which is taken as the location of a single or a pair of switching wires, and the split counter-rotating frequencies of a typical resonator is theoretically obtained. This is done by investigating the split cut-off numbers of the related planar circuit with top and bottom electric walls and a magnetic sidewall. The magnetostatic model adopted in this paper assumes equal fluxes in the up and down magnetized regions but unequal flux densities.