US5039873A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave elements with impedance control circuits
Assignee: Mitsubishi Electric Corp
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Filing: 1990-03-22
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Granted: 1991-08-13
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Expires: 2010-03-22
Abstract
Abstract A microwave element includes an impedance control circuit for controlling the capacitance between the source and the drain of an FET in the off state including a series-connected diode and capacitor connected in parallel between the source and drain of the FET and a circuit for applying a variable bias voltage to the diode. A microwave switch including two FETs includes two impedance control circuits for controlling the capacitances of the FETs. A microwave switched line phase shifter includes two transmission lines of different electrical lengths and four FETs, two of the FETs being connected in series at each of the ends of the two transmission lines. Impedance control circuits for controlling the capacitances of each of the FETs are included. A microwave loaded-line phase shifter includes a main transmission line, two loaded lines having the same electrical length connected to the respective ends of the main line, and impedance control circuits for controlling the capacitances of FETs connected between the loaded lines and ground.
Inventors
- 👤 Yoshinobu Sasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:20
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/18; H01P1/185; H01P1/10; H01P1/15; H03; H03K; H03K17/00; H03K17/14; H03K17/145; H03K17/51; H03K17/56; H03K17/687; H03K17/693
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
61 words
A microwave element comprising: field effect transistor having source, drain, and gate terminals; a series-connected diode and capacitor connected between the source and drain terminals; and means for applying a variable bias voltage to said diode to vary the capacitance of the diode for controlling the capacitance between said source and said drain of said transistor when the transistor is off.
Claim 2
Dependent Claim
61 words
A microwave element comprising: field effect transistor having source, drain, and gate terminals; a series-connected diode and capacitor connected between the source and drain terminals; and means for applying a variable bias voltage to said diode to vary the capacitance of the diode for controlling the capacitance between said source and said drain of said transistor when the transistor is off.
Claim 3
Dependent Claim
143 words
A microwave switch comprising: first and second series-connected field effect transistors, each including a source terminal, a drain terminal, and a gate terminal, a source terminal and a drain terminal of the first and second transistors being connected together; first and second impedance control circuits, each circuit comprising a series-connected diode and capacitor, the first and second circuits being respectively connected between the source and drain terminals of the first and second transistors; means for applying variable bias voltages to each of said diodes to vary the capacitance of each of said diodes and the capacitance between the source and drain terminals of the respective transistors; an input terminal connected to the connection between said first and second transistors; and first and second output terminals at the respective drain and source terminals of said first and second transistors that are not connected together.
Claim 4
Dependent Claim
143 words
A microwave switch comprising: first and second series-connected field effect transistors, each including a source terminal, a drain terminal, and a gate terminal, a source terminal and a drain terminal of the first and second transistors being connected together; first and second impedance control circuits, each circuit comprising a series-connected diode and capacitor, the first and second circuits being respectively connected between the source and drain terminals of the first and second transistors; means for applying variable bias voltages to each of said diodes to vary the capacitance of each of said diodes and the capacitance between the source and drain terminals of the respective transistors; an input terminal connected to the connection between said first and second transistors; and first and second output terminals at the respective drain and source terminals of said first and second transistors that are not connected together.
Claim 5
Dependent Claim
229 words
A microwave switched-line phase shifter comprising: first and second transmission lines having different electrical lengths, each transmission line having first and second ends; first and second field effect transistors, each having a source terminal, a drain terminal, and a gate terminal, one of the source terminals and the drain terminals of the first and second transistors being connected, respectively, to the first and second ends of the said first transmission line; third and fourth field effect transistors, each having a source terminal, a drain terminal, and a gate terminal, one of the source terminals and the drain terminals of the third and fourth transistors being connected, respectively, to the first and second ends of said second transmission line; first, second, third, and fourth impedance control circuits, each circuit comprising a series-connected diode and capacitor, connected respectively between the source and drain terminals of said first, second, third, and fourth transistors; means for applying variable bias voltages to each of said diodes to vary the capacitance of each of said diodes and the capacitances between the source and drain terminals of the respective transistors; an input terminal connected to a series connection of a source terminal and a drain terminal of the first and third transistors; and an output terminal connected to a series connection of a source terminal and a drain terminal of the second and fourth output transistors.
Claim 6
Dependent Claim
229 words
A microwave switched-line phase shifter comprising: first and second transmission lines having different electrical lengths, each transmission line having first and second ends; first and second field effect transistors, each having a source terminal, a drain terminal, and a gate terminal, one of the source terminals and the drain terminals of the first and second transistors being connected, respectively, to the first and second ends of the said first transmission line; third and fourth field effect transistors, each having a source terminal, a drain terminal, and a gate terminal, one of the source terminals and the drain terminals of the third and fourth transistors being connected, respectively, to the first and second ends of said second transmission line; first, second, third, and fourth impedance control circuits, each circuit comprising a series-connected diode and capacitor, connected respectively between the source and drain terminals of said first, second, third, and fourth transistors; means for applying variable bias voltages to each of said diodes to vary the capacitance of each of said diodes and the capacitances between the source and drain terminals of the respective transistors; an input terminal connected to a series connection of a source terminal and a drain terminal of the first and third transistors; and an output terminal connected to a series connection of a source terminal and a drain terminal of the second and fourth output transistors.
Claim 7
Dependent Claim
134 words
A microwave loaded-line phase shifter comprising: a principal transmission line having first and second ends; first and second loaded transmission lines of the same electrical length respectively connected to the first and second ends of said principal transmission line; first and second field effect transistors, each having a source terminal, a drain terminal, and a gate terminal, respectively connected between said first and second loaded transmission lines and ground; first and second impedance control circuits, each circuit comprising a series-connected diode and capacitor connected between the source terminal and the drain terminal of the respective first and second transistors; and means for applying a variable bias voltage to each of said diodes to vary the capacitance of each of said diodes and the capacitances between the source and drain terminals of the respective transistors.
Claim 8
Dependent Claim
134 words
A microwave loaded-line phase shifter comprising: a principal transmission line having first and second ends; first and second loaded transmission lines of the same electrical length respectively connected to the first and second ends of said principal transmission line; first and second field effect transistors, each having a source terminal, a drain terminal, and a gate terminal, respectively connected between said first and second loaded transmission lines and ground; first and second impedance control circuits, each circuit comprising a series-connected diode and capacitor connected between the source terminal and the drain terminal of the respective first and second transistors; and means for applying a variable bias voltage to each of said diodes to vary the capacitance of each of said diodes and the capacitances between the source and drain terminals of the respective transistors.
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) | 1994-08-12 | 1995-02-11 | 1995-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-12 | 1999-02-11 | 1999-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-12 | 2003-02-11 | 2003-08-13 | $7700.00 | Window Closed / Lapsed |