A circulator for radio frequency is provided. The circulator may include a ferrite stripline assembly, which includes a first ferrite layer, a second ferrite layer over the first ferrite layer, and a junction circuit between the first ferrite layer and the second ferrite layer. The circulator may also include a magnet over the second ferrite layer for providing magnetic bias.

Embodiments of synthetic garnet materials having advantageous properties, especially for below resonance frequency applications, are disclosed herein. In particular, embodiments of the synthetic garnet materials can have high Curie temperatures and dielectric constants while maintaining low magnetization. These materials can be incorporated into isolators and circulators, such as for use in telecommunication base stations.

Embodiments of synthetic garnet materials having advantageous properties, especially for below resonance frequency applications, are disclosed herein. In particular, embodiments of the synthetic garnet materials can have high Curie temperatures and dielectric constants while maintaining low magnetization. These materials can be incorporated into isolators and circulators, such as for use in telecommunication base stations.

Disclosed herein is a non-reciprocal circuit element that includes a magnetic rotator and a permanent magnet that applies a magnetic field to the magnetic rotator. The magnetic rotator includes a ferrite core and a center conductor positioned between the ferrite core and the permanent magnet. The center conductor has an upper surface facing the permanent magnet, a side surface perpendicular to the upper surface, and an upper surface side corner part constituted by an end portion of the upper surface and one end portion of the side surface. A fillet is formed at the upper surface side corner part.

A circulator includes: a ferrite plate; a permanent magnet that applies a direct current (DC) magnetic field to the ferrite plate; a first coil, a second coil, and a third coil arranged on the ferrite plate while being insulated from one another, the first coil, the second coil, and the third coil having coil axes intersecting one another; a first port that is electrically continuous with the first coil; a second port that is electrically continuous with the second coil; and a third port that is electrically continuous with the third coil. An inductance of the first coil or the second coil is different from an inductance of the third coil, and an impedance of the first port or the second port is not 50Ω.

A microstrip circulator includes a carrier and a ferrite slab having a first side and a second side. The circulator further includes a first microwave epoxy positioned between the carrier and the first side of the ferrite slab. The circulator further includes a conductor having a center portion with three legs extending therefrom. The circulator further includes a second microwave epoxy positioned between the second side of the ferrite slab and the conductor. The circulator further includes an insulator and a third microwave epoxy positioned between the conductor and the insulator. The circulator further includes a magnet and a fourth epoxy positioned between the insulator and the magnet.

A microstrip circulator includes a carrier and a ferrite slab having a first side and a second side. The circulator further includes a first microwave epoxy positioned between the carrier and the first side of the ferrite slab. The circulator further includes a conductor having a center portion with three legs extending therefrom. The circulator further includes a second microwave epoxy positioned between the second side of the ferrite slab and the conductor. The circulator further includes an insulator and a third microwave epoxy positioned between the conductor and the insulator. The circulator further includes a magnet and a fourth epoxy positioned between the insulator and the magnet.

A wide band radio frequency (RF) circulator is presented. The RF circulator includes at least one stage having four ports, a first end, and a second end, wherein a first port and a third port are connected at the first end of the at least one stage, wherein a second port and a fourth port are connected at the second end of the at least one stage, wherein each of the at least one stage includes a pair of couplers connected through a first delay line and a second delay line, thereby forming a network of couplers in the at least one stage.

Apparatus and methods related to ferrite based circulators are disclosed. A ferrite disk used in a circulator can be configured to reduce intermodulation distortion when routing radio-frequency signals having closely spaced frequencies. Such a reduction in intermodulation distortion can be achieved by adjusting magnetization at the edge portion of the ferrite disk. By way of an example, a ferrite disk with a reduced saturation magnetization (4PiMs) edge portion can reduce intermodulation distortion. Example configurations with such a reduced 4PiMs edge portions are disclosed.

Apparatus and methods related to ferrite based circulators are disclosed. A ferrite disk used in a circulator can be configured to reduce intermodulation distortion when routing radio-frequency signals having closely spaced frequencies. Such a reduction in intermodulation distortion can be achieved by adjusting magnetization at the edge portion of the ferrite disk. By way of an example, a ferrite disk with a reduced saturation magnetization (4PiMs) edge portion can reduce intermodulation distortion. Example configurations with such a reduced 4PiMs edge portions are disclosed.