Abstract :
The modal and eigenvalue approaches of 4-port single-junction circulators are combined to describe the theory and construction, of a waveguide device and a stripline device. The three independent variables used in the case of the waveguide one are a pair of HEspl plusmn1,1,1 open dielectric resonances in a demagnetized ferrite disk, a TM0,1,1 resonance on a metal post, and the magnitude of a direct field to remove the degeneracy between the HEspl plusmn1,1,1 modes. The eigenvalue approach is used to establish systematically each condition one at a time. The variables used in the construction of the stripline junction are a pair of radial n= ±3 degenerate resonances, a radial n=0 resonance, and the amplitude of a direct field to split the degeneracy between the former modes. In this case a circulation condition is found in which it is possible to omit one of the circulation adjustments.