Methods and apparatus for providing a frequency selective limiters (FSL) having a free-standing Yttrium Iron Garnet (YIG) film with first and second opposing surfaces. A metal plane is disposed on one surface of the YIG film to provide the YIG film with a metalized surface. At least one transducer is disposed on the other surface of the YIG film with a respective ends coupled to the metalized surface of the YIG film.

A magnetic structure for an electromagnetic resonator is provided. The magnetic structure comprises at least a solenoid and a permanent magnet, wherein the solenoid and the permanent magnet are concentrically arranged to each other such that the magnetic field lines provided by the permanent magnet are at least essentially perpendicular to magnetic field lines of a magnetic field generated by the solenoid. The arrangement of the permanent magnet and the solenoid may be housed by an element with a high magnetic permeability.

A tunable frequency selective limiter is disclosed. In one or more embodiments, the tunable frequency selective limiter includes a first electrically conductive path. The tunable frequency selective limiter also includes a ferrimagnetic layer disposed adjacent to the first electrically conductive path. The tunable frequency selective limiter further includes a second electrically conductive path coiled around the first electrically conductive path and the ferrimagnetic layer. An electromagnetic current transmitting through the second electrically conductive path produces a magnetic field coupled to the ferrimagnetic layer. The tunable frequency selective limiter further includes a dielectric layer, wherein the ferrimagnetic layer is disposed on the dielectric layer. The portions of the second electrically conductive path that are at the interface of the dielectric layer and the ferrimagnetic layer may be embedded into the dielectric layer or may be disposed on the surface of the dielectric layer.

A tunable frequency selective limiter is disclosed. In one or more embodiments, the tunable frequency selective limiter includes a first electrically conductive path. The tunable frequency selective limiter also includes a ferrimagnetic layer disposed adjacent to the first electrically conductive path. The tunable frequency selective limiter further includes a second electrically conductive path coiled around the first electrically conductive path and the ferrimagnetic layer. An electromagnetic current transmitting through the second electrically conductive path produces a magnetic field coupled to the ferrimagnetic layer. The tunable frequency selective limiter further includes a dielectric layer, wherein the ferrimagnetic layer is disposed on the dielectric layer. The portions of the second electrically conductive path that are at the interface of the dielectric layer and the ferrimagnetic layer may be embedded into the dielectric layer or may be disposed on the surface of the dielectric layer.

A high frequency yttrium iron garnet oscillator is described that comprises a coplanar yttrium iron garnet resonator. The coplanar yttrium iron garnet resonator has an yttrium iron garnet sphere, a coplanar coupling structure and a coplanar waveguide. The coplanar coupling structure is integrated with the coplanar waveguide. The coplanar coupling structure is coupled to the yttrium iron garnet sphere. Further, a method of manufacturing a high frequency yttrium iron garnet oscillator is described.

Disclosed herein is a nonreciprocal circuit element that includes a permanent magnet, a magnetic material having an insulating property, a magnetic rotator sandwiched between the permanent magnet and the magnetic material, and an external terminal. The magnetic rotator includes a center conductor connected to the external terminal, and first and second ferrite cores sandwiching the center conductor. The external terminal covers a side surface of the magnetic material without covering a side surface of the permanent magnet.

Disclosed herein is a nonreciprocal circuit element that includes a permanent magnet, a magnetic material having an insulating property, a magnetic rotator sandwiched between the permanent magnet and the magnetic material, and an external terminal. The magnetic rotator includes a center conductor connected to the external terminal, and first and second ferrite cores sandwiching the center conductor. The external terminal covers a side surface of the magnetic material without covering a side surface of the permanent magnet.

A magnetoresistive effect device includes an input port, an input-side signal line, an MR unit including a magnetoresistive effect element and a magnetic-field generating signal line, and an output unit including a magnetoresistive effect element, an output-side signal line, and an output port. The magnetoresistive effect device further includes a DC application terminal. The magnetoresistive effect element is connected to the output port via the output-side signal line in the output unit. The input-side signal line is arranged so that a high frequency magnetic field generated from the input-side signal line is applied to the magnetoresistive effect element in the MR unit. In the MR unit, the magnetoresistive effect element is connected to the magnetic-field generating signal line. The magnetic-field generating signal line is arranged so that a high-frequency magnetic field generated from magnetic-field generating signal line is applied to the magnetoresistive effect element in the output unit.

A magnetoresistive effect device includes an input port, an input-side signal line, an MR unit including a magnetoresistive effect element and a magnetic-field generating signal line, and an output unit including a magnetoresistive effect element, an output-side signal line, and an output port. The magnetoresistive effect device further includes a DC application terminal. The magnetoresistive effect element is connected to the output port via the output-side signal line in the output unit. The input-side signal line is arranged so that a high frequency magnetic field generated from the input-side signal line is applied to the magnetoresistive effect element in the MR unit. In the MR unit, the magnetoresistive effect element is connected to the magnetic-field generating signal line. The magnetic-field generating signal line is arranged so that a high-frequency magnetic field generated from magnetic-field generating signal line is applied to the magnetoresistive effect element in the output unit.

A method for minimizing center frequency shift and linearity errors encountered in YIG filters, comprising the following steps: automatically generating data packages in test unit depending on the user request or containing all filter characteristic states and transmitting them to the driver circuit, adjusting the desired voltage level by means of the digital to analog converters contained in the structure of the data packages received by the driver circuit, and transmitting the adjusted voltage level to the YIG filter, measuring filter characteristics (scattering parameters) corresponding to the data packages transmitted to the YIG filter in the analyser, in order to calculate the center frequency shift of the filter, determining the center frequency and linearity calculations, and recording the characteristic features measured by the analyser in the test unit.