Slot line between oppositely-magnetized ferrite layers for broadband, high-nonreciprocity phase shifters

A novel phase shifting structure that exhibits both broadband operation and high nonreciprocity is presented. This structure comprises a slot line between two oppositely magnetized ferrite substrates. A full-wave, spectral-domain analysis is used, where Green's functions are formulated using a transmission matrix approach. By eliminating the use of relatively thick high-dielectric substrates, a bandwidth of 3:1 and a differential phase of 50 degrees /cm are feasible. The addition of thin layers of high-dielectric material is shown to increase the differential phase to over 100 degrees /cm without significantly reducing the bandwidth.<>