COMPUTATION OF PROPER AND IMPROPER MODES IN MULTILAYERED BIANISOTROPIC WAVE-GUIDES

An efficient numerical method is presented to determine the loci of bo th the proper and complex improper modes of a multilayered bianisotrop ic planar waveguide. The propagation constants of the waveguide modes are expressed in terms of the zeros of a specific analytic function. T he use of appropriate integration zero-searching methods is proposed s ince information about the possible number of complex improper modes c annot be previously extracted. The general formulation presented here has been applied to the study of the complex improper modes of single and two-layer structures containing magnetized ferrites. It has been f ound that the transition from physical proper to complex improper mode s is made throughout a nonphysical real improper mode.