US4754234A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Broadband distributed amplifier for microwave frequences
Assignee: US Philips Corp
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Filing: 1987-02-25
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Granted: 1988-06-28
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Expires: 2007-02-25
Abstract
Abstract A broadband distributed amplifier comprised of a plurality of field effect transistors whose gates are connected to junctions between serially-connected inductors forming a gate transmission line, whose drains are connected to junctions between serially-connected inductors forming a drain transmission line, and whose sources are connected to ground. The distribution of the amplifier stages along the gate and drain transmission lines is effected such that these transmission lines are periodically loaded by their own impedances and by the transistor gate and drain capacitances, thus forming artificial lines, and such that a microwave frequency input signal applied to the input of the gate transmission line effects the production of an amplified microwave frequency output signal at the output of the drain transmission line. The gate and drain transmission line output and input, respectively, are terminated by loads. The drain transmission line input only includes biasing means, whereas the gate transmission line output includes means for compensating for the characteristic impedance variations of the artificial line as a function of the frequency.
Inventors
- 👤 Patrice Gamand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:48
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/08; H03F1/18; H03F3/00; H03F3/60; H03F3/605; H03F3/607
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
214 words
In a broadband distributed amplifier of the type comprising: a. a first transmission line including an input end for receiving an applied microwave-frequency input signal, an output end, a plurality of inductors electrically connected in series between said ends, and a plurality of junctions disposed periodically along said line; b. a second transmission line including an input end, an output end for providing an amplified microwave-frequency output signal, a plurality of inductors electrically connected in series between said ends, and a plurality of junctions disposed periodically along said line; and c. a plurality of field effect transistors, each including a gate electrically connected to a respective one of the junctions in the first transmission line, a drain electrically connected to a respective one of the junctions in the second transmission line, and a source electrically connected to a reference potential; the improvement comprising means for maximizing the useable frequency range of the amplifier, said means including: d. an impedance-compensating circuit electrically connected to the output end of the first transmission line, said circuit having a frequency-dependent input impedance which varies correspondingly with a frequency-dependent characteristic impedance of the transmission lines and suppresses signal reflections at said output end; and e. a biasing circuit electrically connected to the input end of the second transmission line.
Claim 2
Dependent Claim
214 words
In a broadband distributed amplifier of the type comprising: a. a first transmission line including an input end for receiving an applied microwave-frequency input signal, an output end, a plurality of inductors electrically connected in series between said ends, and a plurality of junctions disposed periodically along said line; b. a second transmission line including an input end, an output end for providing an amplified microwave-frequency output signal, a plurality of inductors electrically connected in series between said ends, and a plurality of junctions disposed periodically along said line; and c. a plurality of field effect transistors, each including a gate electrically connected to a respective one of the junctions in the first transmission line, a drain electrically connected to a respective one of the junctions in the second transmission line, and a source electrically connected to a reference potential; the improvement comprising means for maximizing the useable frequency range of the amplifier, said means including: d. an impedance-compensating circuit electrically connected to the output end of the first transmission line, said circuit having a frequency-dependent input impedance which varies correspondingly with a frequency-dependent characteristic impedance of the transmission lines and suppresses signal reflections at said output end; and e. a biasing circuit electrically connected to the input end of the second transmission line.
Claim 3
Dependent Claim
39 words
An amplifier as in claim 1 where the impedance-compensating circuit comprises a plurality of transmission line sections electrically connected in series and an open-circuited transmission line section electrically connected to a junction disposed between successive ones of said sections.
Claim 4
Dependent Claim
28 words
An amplifier as in claim 2 where the impedance-compensating circuit comprises two of the serially-connected transmission line sections and at least one of the open-circuited transmission line sections.
Claim 5
Dependent Claim
57 words
An amplifier as in claim 1, 2 or 3 where the biasing circuit comprises a plurality of transmission line sections electrically connected in series and a plurality of capacitors each having one end electrically connected to a respective junction disposed between successive ones of said sections and having an opposite end electrically connected to a reference potential.
Claim 6
Dependent Claim
43 words
An amplifier as in claim 1, 2 or 3 where the output end of the first transmission line and the input end of the second transmission line are each terminated in a load comprising a resistor electrically connected in series with a capacitor.
Claim 7
Dependent Claim
19 words
An amplifier as in claim 1, 2 or 3 where the entire amplifier is disposed on an insulating substrate.
Claim 8
Dependent Claim
15 words
An amplifier as in claim 5 where the substrate consists essentially of a ceramic material.
Claim 9
Dependent Claim
14 words
An amplifier as in claim 7 where the substrate consists essentially of aluminum oxide.
Claim 10
Dependent Claim
25 words
An amplifier as in claim 1, 2 of 3 where the entire amplifier is monolithically integrated on a substrate consisting essentially of a III-V compound.
Claim 11
Dependent Claim
12 words
An amplifier as in claim 9 where the compound is gallium arsenide.
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) | 1991-06-28 | 1991-12-28 | 1992-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-28 | 1995-12-28 | 1996-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-28 | 1999-12-28 | 2000-06-28 | $7700.00 | Window Closed / Lapsed |