Standing Wave Solutions and Cutoff Numbers of Planar WYE and Equilateral Triangle Resonators

Important planar resonators with top and bottom electric walls and a magnetic sidewall that have the symmetries of the three‐port junction circulator are the wye and equilateral triangle resonators. This chapter summarizes the dominant mode cutoff number and standing wave pattern of each arrangement. The equipotential lines and cutoff numbers of the first three modes of a planar wye resonator have been computed by having recourse to a finite element (FE) program. One possible variation of the wye resonator is the disk‐stub gyromagnetic arrangement consisting of a circular plate to which are connected three short unit elements. The cutoff numbers of the equilateral triangular planar resonators enter into the description of prism cavities met in the design of fixed and switched junction circulators. While it is difficult to visualize rotation in such resonators, circulation solutions may therefore be established by constructing a linear combination of isotropic resonators.