Dielectric slab matched ferrite gyrator

A 180° nonreciprocal ferrite phase shifter with stepped dielectric impedance transformer sections at both ends is designed using the method of field expansion into eigenmodes. The rigorous optimisation method includes the higher-order mode interaction between the step discontinuities. The design achieves compact and simple components, as relatively thick, and consequently short, uniform ferrite slabs of standard dimensions may utilised. A computer-optimized design example provides about 180° ± 1° nonreciprocal differential phase shift between 12.2 and 12.8 GHz together with more than 24dB return loss.