Stripline Ferrite Devices

A stripline instantaneous wideband nonreciprocal hybrid using ferrite material is described. A simple theory of operation, potential use as a broadband circulator and switch is described. The design and data on a laboratory model operating from 3 GHz to 9 GHz is presented. The theory and results on a three-port switchable S-band microstrip circulator suitable for microwave integrated circuits is also reported. The circulator had a 2 db insertion loss and a 2 bandwidth. Although the insertion loss could be decreased by more refined etching and polishing techniques, the high Q inherent in this ring principle of operation severely limits the bandwidth. Rf sputtering process to deposit dielectric materials for obtaining thin film capacitors is also described.