Temperature stabilization of a lumped element circulator without an apparent compensating element

An experiment has shown that a thermostable circulator can be fabricated by inserting a small capacitor between the ground and the ferrite. The analysis and the characteristics estimated using the element eigenvalues have confirmed the experimental result. A circulator based on the above thermostabilization has shown that the bandwidth was expanded more than twofold in the temperature range from -25/spl deg/C to 85/spl deg/C.