Influence of nonuniform magnetic field on a ferrite junction circulator

We have analytically formulated the problem that a ferrite circulator junction is biased by a nonuniform magnetic field. Interport impedances of the junction can, therefore, be solved numerically. Nonuniform-bias field will reduce the transmission bandwidth, and the circulation condition is apt to be altered if the bias field shows nonuniformity near the center of the junction. Our calculation compares very well with measurements.