Modeling of Magnetostatic Wave Delay Lines with Side Coupling Between Transducers and Ferrite Film

The paper presents a new analytical method for solving electrodynamic problems of the excitation of waves in semi-infinite ferrite waveguides magnetized in an arbitrary direction by a uniform or transversely nonuniform field. Edge effects at the end of the waveguide caused by static demagnetizing are taken into account. The solution is derived from the linearized Landau-Lifshits equation using an orthogonality condition for eigenwaves of a magnetization. Applications of the theory are demonstrated for modeling and numerical calculations of frequency responses of magnetostatic wave delay lines with the side coupling of stripline transducers to a ferrite film. The optimum position of transducers, which provides the minimum insertion loss of delay lines, is determined. It is proved that a side coupling scheme enables to obtain lower loss of delay lines, then other methods usually used. Results of the theory can be also applied for modeling of phased antenna arrays using ferrite waveguides.