US3879677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tuned oscillator circuit having a tuned filter output
Assignee: Varian Medical Systems Inc
•
Filing: 1973-07-20
•
Granted: 1975-04-22
•
Expires: 1993-07-20
Abstract
Abstract A transistor microwave oscillator circuit is provided with a YIG resonator device coupled to one of the transistor terminals. The YIG device resonates at a frequency established by a magnetic field applied thereacross and determines the oscillation frequency of the transistor circuit. Another YIG device is provided as a frequency responsive output transformer and functions as a high Q filter. This YIG transformer is positioned within the same applied magnetic field and has a resonant frequency identical to the YIG resonator. That is, the center frequency of the bandpass filter is the same as the oscillator frequency. As the applied magnetic field is varied, both the oscillation frequency of the transistor and the center frequency of the filter vary an identical amount. This frequency tracking insures that the oscillations are optimally passed by the filter, while off-frequencies are maximally attenuated. Further, the YIG transformer functions as an output impedance matching device. The YIG transformer is loop or coil-coupled to the transistor output terminal and loop-coupled to the load. These coupling coils may easily be modified as to number of turns and proximity to the YIG spheres to effect an optimal impedance match in a manner similar to conventional transformer coupling.
Inventors
- 👤 Charles A Arnold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:08
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/18; H03B5/1882; H03B5/1888
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
142 words
An oscillator circuit comprising: means for providing at least one magnetic field of a predetermmined strength: a ferrimagnetic resonator device positioned within said magnetic field, and exhibiting a gyromagnetic resonance frequency in response to the strength of said magnetic field; an electronic amplifier means having a power input terminal for connection to an external power source, and having a signal input terminal separate from said power input terminal for connection to a signal source, said amplifier means being adapted to cause said signal input to control power from said source; means connected to signal input terminal for deriving an input signal from said ferrimagnetic device; and at least one frequency responsive ferrimagnetic output device positioned within the at least one magnetic field and in electrical communication with the amplifying means for passing the said gyromagnetic resonance frequency and for rejecting off frequencies.
Claim 2
Dependent Claim
142 words
An oscillator circuit comprising: means for providing at least one magnetic field of a predetermmined strength: a ferrimagnetic resonator device positioned within said magnetic field, and exhibiting a gyromagnetic resonance frequency in response to the strength of said magnetic field; an electronic amplifier means having a power input terminal for connection to an external power source, and having a signal input terminal separate from said power input terminal for connection to a signal source, said amplifier means being adapted to cause said signal input to control power from said source; means connected to signal input terminal for deriving an input signal from said ferrimagnetic device; and at least one frequency responsive ferrimagnetic output device positioned within the at least one magnetic field and in electrical communication with the amplifying means for passing the said gyromagnetic resonance frequency and for rejecting off frequencies.
Claim 3
Dependent Claim
142 words
An oscillator circuit comprising: means for providing at least one magnetic field of a predetermmined strength: a ferrimagnetic resonator device positioned within said magnetic field, and exhibiting a gyromagnetic resonance frequency in response to the strength of said magnetic field; an electronic amplifier means having a power input terminal for connection to an external power source, and having a signal input terminal separate from said power input terminal for connection to a signal source, said amplifier means being adapted to cause said signal input to control power from said source; means connected to signal input terminal for deriving an input signal from said ferrimagnetic device; and at least one frequency responsive ferrimagnetic output device positioned within the at least one magnetic field and in electrical communication with the amplifying means for passing the said gyromagnetic resonance frequency and for rejecting off frequencies.
Claim 4
Dependent Claim
142 words
An oscillator circuit comprising: means for providing at least one magnetic field of a predetermmined strength: a ferrimagnetic resonator device positioned within said magnetic field, and exhibiting a gyromagnetic resonance frequency in response to the strength of said magnetic field; an electronic amplifier means having a power input terminal for connection to an external power source, and having a signal input terminal separate from said power input terminal for connection to a signal source, said amplifier means being adapted to cause said signal input to control power from said source; means connected to signal input terminal for deriving an input signal from said ferrimagnetic device; and at least one frequency responsive ferrimagnetic output device positioned within the at least one magnetic field and in electrical communication with the amplifying means for passing the said gyromagnetic resonance frequency and for rejecting off frequencies.
Claim 5
Dependent Claim
30 words
The oscillator circuit of claim 1 wherein the means for providing at least one magnetic field provides a single magnetic field within which all of the ferrimagnetic devices are positioned.
Claim 6
Dependent Claim
39 words
The oscillator circuit of claim 2 wherein the single magnetic field is adjustable in strength throughout a predetermined range for establishing a spectrum of gyromagnetic resonance frequencies over which the ferrimagnetic devices tune in response to the magnetic field.
Claim 7
Dependent Claim
16 words
The oscillator circuit of claim 3 wherein the tuned ferrimagnetic devices are yttrium iron garnet spheres.
Claim 8
Dependent Claim
16 words
The oscillator circuit of claim 4 wherein the YIG spheres are single crystal and Gallium doped.
Claim 9
Dependent Claim
47 words
The oscillator circuit of claim 4 wherein the tuned YIG resonator is loop coupled to the amplifying means, and the at least one output YIG is a single YIG loop coupled, tuned bandpass filter having a center frequency at the gyromagnetic resonance frequency of the resonator YIG.
Claim 10
Dependent Claim
33 words
The oscillator circuit of claim 6 wherein the at least one output YIG comprises a plurality of loop coupled YIG bandpass filters all tuned to the gyromagnetic resonance frequency of the resonator YIG.
Claim 11
Dependent Claim
32 words
The oscillator circuit of claim 6 wherein the coupling loops of the at least one YIG tuned bandpass filter are positioned to determine the input impedance and output impedance of the filter.
Claim 12
Dependent Claim
38 words
The oscillator circuit of claim 8 wherein the input impedance of the YIG filter is matched to the output impedance of the amplifying means and the output impedance of the YIG filter is adjustable to maximize power output.
References Cited (Backward Citations)
US2817761A
Cited
US2889460A
Cited
US3290625A
Cited
US3274588A
Cited
US3435385A
Cited
US3544918A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-21 | 1978-10-21 | 1979-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-21 | 1982-10-21 | 1983-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-21 | 1986-10-21 | 1987-04-22 | $7700.00 | Window Closed / Lapsed |