Millimeter wave microstrip nonreciprocal phase shifter

Abstract

A microstrip nonreciprocal latching phase shifter has a ferrite rod with ramp-shaped dielectric waveguide members at the ends thereof mounted on one surface of a microstrip dielectric substrate having a ground plane on the opposite surface thereof. The dielectric constants of the ramp members and the rod are substantially the same and the substrate dielectric constant is substantially less than the dielectric constant of the ramp members. A dielectric plate is on top of the rod. A microstrip conductor mounted on the substrate, the ramp members and the plate in axial alignment with the rod extends between the ends of the substrate. The rod has a rectangular longitudinally-extending passageway therein filled by a dielectric core insert having a dielectric constant greater than the dielectric constant of the rod. A single control wire is disposed in and aligned with the core insert. By selectively pulsing the control wire with reversible polarity current pulses, circular magnetic fields of reversible directions are created in the toroidal-shaped flux path formed in the rod around the wire, so that the rod acts as a twin slab type of phase shifter with respect to millimeter wave energy passing from one end of the microstrip conductor to the other end thereof.