A low loss unidirectional conductive sheet using magnetic field biasing and electron spin precession for coupling RF power to ferrite resonators, comprising the step of placing a plurality of ferrite resonators in a bias magnetic field to excite the electron spins of the materials of said ferrite resonators into precession.

An apparatus and method for building and operating of a YIG-based filter-attenuator module with closed-loop control. The module combines both signal filtering and amplitude control functions by utilizing an yttrium-iron-garnet (YIG) resonator. A technique for a closed-loop calibration and control also disclosed. This apparatus and method provides a cost effective harmonic rejection/amplitude control solution for microwave test-and-measurement instruments such as signal generators and spectrum analyzers.

A dual-resonator YIG oscillator with a main YIG resonator and a stabilizing YIG resonator both suspended in a common magnetic field. The main YIG resonator takes on the high-Q factor aspects of the oscillator, while the stabilizing YIG resonator helps stabilize the operation of the main YIG resonator, and also allows the main YIG resonator operate at higher magnetic field strengths, achieving higher frequency operation. The stabilizing YIG resonator also enables the oscillator's active device to operate in a more linear, lower phase noise, regime. As compared to conventional YIG oscillators, the disclosed dual resonator YIG oscillator provides significant performance improvements, such as higher frequency operation, lower power consumption, higher tuning speed, and lower phase noise.

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.

A low loss unidirectional conductive sheet using magnetic field biasing and electron spin precession for coupling RF power to ferrite resonators, comprising the step of placing a plurality of ferrite resonators in a bias magnetic field to excite the electron spins of the materials of said ferrite resonators into precession.

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.

The present invention concerns a device (1) for an atomic clock. The device has a printed circuit board (20), a heating source, and microwave conductor. The printed circuit board (20) includes a conductive piece (10) for both interrogating and heating a gas in a cell of an atomic clock. The piece (10) has a gap (11), and is arranged for containing the cell (2), so as to directly touch the cell (2) in at least one point. The heating source (40, 60) generates heat, and is connected to the piece (10). The microwave conductor (12) is arranged to be connected to the piece (10) so as to send to the piece (10) a microwave signal for interrogating the atoms of the gas in the cell (2). This device performs more than one function (e.g. heating and interrogating) and simplify the manufacturing of the atomic clock.

A radio frequency (RF) wave generator includes a nonlinear transmission line and a pulse generator. The nonlinear transmission line has in order an input section, a magnetic section, and an output section. The magnetic section includes a nonlinear magnetic material. The pulse generator is configured to provide an input pulse to the input section which is converted to an RF wave by the nonlinear transmission line. A waveform of the input pulse is such that the generated RF wave is parametrically amplified.

Circuits, methods, and apparatus that can provide oscillator circuits that have reduced phase noise. An example can provide a yttrium-iron-garnet oscillator in a loop with a loop amplifier and a phase-shift circuit. The yttrium-iron-garnet oscillator can act as a resonator. Quadrature outputs of the yttrium-iron-garnet oscillator can drive a phase detector that can provide a control signal to the phase-shift circuit. The phase-shift circuit can then reduce or cancel phase noise in the loop, thereby enabling the loop to provide a reference signal having reduced phase noise.