Development of high frequency ferrite phase-shifter

A phase-shifter was fabricated on a c-texture Zn2Y (Zn2Ba2Fe12O22) single c rystal substrate, and tested over microwave frequencies from 2 to 35 GHz an d for biasing magnetic fields from 0.2 to 5 kOe. The differential phase-shi ft rate was 90 degrees /kOe.mm at a microwave frequency of 20 GHz and a mag netic bias-filed of 1.3 kOe. This device showed that it is possible to redu ce the bias-field requirement efficiently and simply by utilizing the large in-plane anisotropy in Y-type hexaferrites and magnetostatic modes. A simp le model based on the conjugate method for a TEM wave gave a reasonable mat ch with the measured performance of the device, when the uniaxial magnetic anisotropy and magnetostatic modes were included.