US4743865A
Expired / Lapsed
US
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Quartz-crystal microwave oscillator of the common-emitter transmission type with two transistors and a predetermined loaded Q factor
Assignee: D'ELECTRONIQUE ET DE PIEZOELECTRICITE CEPE Cie
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Filing: 1987-07-09
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Granted: 1988-05-10
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Expires: 2007-07-09
Abstract
Abstract The resonant frequency of a quartz-crystal microwave oscillator is the fundamental frequency in the partial mode of the crystal and makes it possible to maintain the loaded Q of the resonator at a high value. This microwave oscillator is provided with two amplifying stages and has a signal-to-noise ratio of the order of 160 dB.
Inventors
- 👤 Jacques Chauvin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:38
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; H03B5/32; H03B5/36; H03B5/366; H03B5/368; H03B2200/00; H03B2200/003; H03B2200/004
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
142 words
A quartz-crystal microwave oscillator which is capable of operating at frequencies within the range of 750 to 1500 MHz and the feedback loop of which satisfies the Barkhausen conditions, wherein: the feedback loop includes at least the following elements placed in series and in this order: a first matching quadripole, a first amplifying stage, a second matching quadripole, a resonator, a third matching quadripole, a second amplifying stage, a fourth matching quadripole and a power divider; the amplifying stages each have one transistor mounted with a common emitter connection; the matching quadripoles make it possible to match the input and output impedances of the amplifying stage with the other elements of the feedback loop; the resonator is constituted mainly by a quartz crystal; the power divider serves to collect the output signal of the oscillator for onward transmission to a utilization circuit.
Claim 2
Dependent Claim
142 words
A quartz-crystal microwave oscillator which is capable of operating at frequencies within the range of 750 to 1500 MHz and the feedback loop of which satisfies the Barkhausen conditions, wherein: the feedback loop includes at least the following elements placed in series and in this order: a first matching quadripole, a first amplifying stage, a second matching quadripole, a resonator, a third matching quadripole, a second amplifying stage, a fourth matching quadripole and a power divider; the amplifying stages each have one transistor mounted with a common emitter connection; the matching quadripoles make it possible to match the input and output impedances of the amplifying stage with the other elements of the feedback loop; the resonator is constituted mainly by a quartz crystal; the power divider serves to collect the output signal of the oscillator for onward transmission to a utilization circuit.
Claim 3
Dependent Claim
15 words
An oscillator according to claim 1, wherein the first matching quadripole includes a high-pass filter.
Claim 4
Dependent Claim
15 words
An oscillator according to claim 1, wherein the third matching quadripole includes a high-pass filter.
Claim 5
Dependent Claim
30 words
An oscillator according to claim 1, wherein the parasitic capacitance of the quartz crystal is compensated at the operating frequency by a circuit which includes at least one inductance coil.
Claim 6
Dependent Claim
15 words
An oscillator according to claim 1, wherein the power divider is of the Wilkinson type.
Claim 7
Dependent Claim
26 words
An oscillator according to claim 1, wherein the feedback loop also includes a phase line having a length so determined as to satisfy the phase condition.
Claim 8
Dependent Claim
15 words
An oscillator according to claim 1, wherein the feedback loop includes a voltage-controlled phase modulator.
Claim 9
Dependent Claim
24 words
An oscillator according to claim 7, wherein the phae modulation is obtained by means of a varactor which is subjected to the control voltage.
Claim 10
Dependent Claim
66 words
An oscillator according to claim 2, wherein the third matching quadripole includes a high-pass filter, the parasitic capacitance of the quartz crystal is compensated at the operating frequency by a circuit which includes at least one inductance coil, the power divider is of the Wilkinson type, and the feedback loop also includes a phase line having a length so determined as to satisfy the phase condition.
Claim 11
Dependent Claim
24 words
An oscillator according to claim 9, wherein the feedback loop includes in addition a phase modulator which is voltage-controlled by means of a varactor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-10 | 1991-11-09 | 1992-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-10 | 1995-11-09 | 1996-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-10 | 1999-11-09 | 2000-05-10 | $7700.00 | Window Closed / Lapsed |