High-power waveguide circulators using quarter-wave long composite ferrite/dielectric resonators

Abstract
The thermal capacity of junction circulators operating at large CW power levels may be improved by employing mixed ferrite dielectric resonators in their construction. The paper describes a new quarter-wave long composite resonator for use in waveguide circulators. It is obtained by establishing the quarter-wavelong dimensions of the resonator by cascading ferrite and dielectric discs instead of using a single ferrite disc. The relation between the filling factor, the magnetisation of the resonator and the specification of the device is derived as a preamble to the design of a number of circulators. The theoretical magnetisation provides an upper bound on the required experimental value. Such a circulator has been tested at 6500 W CW at 2.35 GHz. The resonator described in the paper may also be used in the design of large peak-power circulators, where the magnetic variables are chosen to suppress nonlinear effects which can occur at large signal level in ferrite devices. This configuration has been tested at 400 kW peak at 3.0 GHz.

This publication has 0 references indexed in Scilit: