A 1.7GHz Lumped-Element Circulator Stable Over a Wide Range of Temperature

This paper describes a broadband thin-film lumped-element circulator stabilized over a wide range of temperatures using a newly-developed ferrite material with a low temperature coefficient. The experimental circulator exhibits a bandwidth of about 420MHz over a wide temperature range of from -10/spl deg/C to 60/spl deg/c, in which VSWR and loss are less than 1.2 and 1.0dB, respectively.