The 3-port circulator is a unique nonreciprocal symmetrical junction having one typical input port, one output port and one decoupled port. The device can be modelled as a magnetized ferrite or garnet gyromagnetic resonator having 3-fold symmetry connected or coupled to three transmission lines or waveguides. The introduction of such a resonator at the junction of three E- or H-plane waveguides or finline circuits readily produces a degree-1 circulation. In practice, the resonator is embedded in a filter circuit to produce a degree-2 or 3 frequency response. Several topologies of the 3-port circulator are presented, describing their operation based on superposition.
|Pages (from-to)||41-42, 45|
|Journal||Microwave Engineering Europe|
|Publication status||Published - May 1998|