US4733170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave power sensors
Assignee: Marconi Instruments Ltd
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Filing: 1986-05-28
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Granted: 1988-03-22
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Expires: 2006-05-28
Abstract
Abstract A microwave power sensor utilizing a semiconductor power absorption element which is mounted on a fin-line structure within a waveguide channel. In order to check calibration of the sensor, a coaxial line is used to feed a relatively low frequency reference signal to the power sensor. The power element is positioned between the input port of the waveguide and a coaxial line input port at which the reference signal is applied. The use of a precise and accurate reference signal enables the power sensor to be used for microwave measurements.
Inventors
- 👤 Paul A. McAllister
- 👤 Thomas G. McConnell
- 👤 Frederick R. Weston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:13
CPC Classifications
G; G01; G01R; G01R21/00; G01R21/01; G01R21/02; G01R21/04
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
110 words
A microwave power sensor including a waveguide section; power absorption means having two power elements located within said waveguide section, said power absorption means absorbing microwave power applied thereto; a fin line structure located within said waveguide section, said power absorption means being mounted on said structure for coupling to a source of incident microwave power; and means for applying a reference power signal at a sub-microwave frequency to the absorption means via a transmission line having a predetermined characteristic impedance, the two power elements of said power absorption means being connected effectively in series to receive said microwave power and effectively in parallel to receive said reference power signal.
Claim 2
Dependent Claim
110 words
A microwave power sensor including a waveguide section; power absorption means having two power elements located within said waveguide section, said power absorption means absorbing microwave power applied thereto; a fin line structure located within said waveguide section, said power absorption means being mounted on said structure for coupling to a source of incident microwave power; and means for applying a reference power signal at a sub-microwave frequency to the absorption means via a transmission line having a predetermined characteristic impedance, the two power elements of said power absorption means being connected effectively in series to receive said microwave power and effectively in parallel to receive said reference power signal.
Claim 3
Dependent Claim
20 words
A sensor as claimed in claim 1 and wherein the transmission line comprises a planar conductor on a dielectric substrate.
Claim 4
Dependent Claim
36 words
A sensor as claimed in claim 1 wherein the characteristic impedance of said transmission line is less than that of the portion of the fin line structure which couples microwave power to said power absorption means.
Claim 5
Dependent Claim
30 words
A sensor as claimed in claim 1, and wherein the transmission line is positioned on the side of said power absorption means opposite to that of the fin line structure.
Claim 6
Dependent Claim
28 words
A sensor as claimed in claim 2, wherein a coaxial cable is connected to said planar conductor to feed said reference power signal to the power absorption means.
Claim 7
Dependent Claim
24 words
A sensor as claimed in claim 5 and wherein a d.c. decoupling capacitor is connected between the coaxial cable and said power absorption means.
Claim 8
Dependent Claim
33 words
A sensor as claimed in claim 1 and wherein the fin line structure comprises a dielectric substrate which carries a pair of conductors separated by a narrow gap running centrally along the waveguide.
Claim 9
Dependent Claim
37 words
A sensor as claimed in claim 1 wherein each of said power elements includes a resistor adapted to absorb heat from incident microwave energy, and means for producing a signal related to the temperatures of said resistors.
Claim 10
Dependent Claim
17 words
A sensor as claimed in claim 3 wherein said power absorption means comprises a semiconductor thermoelectric element.
Claim 11
Dependent Claim
26 words
A sensor as claimed in claim 4 wherein said power absorption means comprises two thermoelectric elements, the respective thermoelectric e.m.f.'s of which are arranged to add.
Claim 12
Dependent Claim
32 words
A sensor as claimed in claim 10 wherein the two thermoelectric elements are connected effectively in series to receive said microwave power and effectively in parallel to receive said reference power signal.
Claim 13
Dependent Claim
36 words
A sensor as claimed in claim 11 wherein said power absorption means comprises two thermoelectric elements mounted on a common semiconductor substrate, with the reference power signal being applied to a mid-point of the series connection.
Claim 14
Dependent Claim
109 words
A microwave power sensor including a waveguide section; a power absorption device located within said waveguide section, said power absorption device absorbing microwave power applied thereto; a fin line structure on which said power absorption device is mounted for coupling to a source of incident microwave power; means for applying a reference power signal at a sub-microwave frequency to said power absorption device, said means including a transmission line comprising a dielectric substrate having a planar conductor mounted thereon and a coaxial cable connected to said planar conductor for receiving said reference power signal; and a d.c. decoupling capacitor connected between said coaxial cable and said power absorption device.
Claim 15
Dependent Claim
109 words
A microwave power sensor including a waveguide section; a power absorption device located within said waveguide section, said power absorption device absorbing microwave power applied thereto; a fin line structure on which said power absorption device is mounted for coupling to a source of incident microwave power; means for applying a reference power signal at a sub-microwave frequency to said power absorption device, said means including a transmission line comprising a dielectric substrate having a planar conductor mounted thereon and a coaxial cable connected to said planar conductor for receiving said reference power signal; and a d.c. decoupling capacitor connected between said coaxial cable and said power absorption device.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-22 | 1991-09-21 | 1992-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-22 | 1995-09-21 | 1996-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-22 | 1999-09-21 | 2000-03-22 | $7700.00 | Window Closed / Lapsed |