Patent US7035616B2 successfully refreshed from Google Patents.
US7035616B2
Expired / Lapsed
US
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Two-stage variable-gain mixer employing shunt feedback
Assignee: International Business Machines Corp
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Filing: 2002-01-04
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Granted: 2006-04-25
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Expires: 2022-01-04
Abstract
Abstract A demodulator which includes an active balun circuit and at least one mixer driven by the active balun circuit. The active balun circuit includes a negative shunt feedback arrangement.
Inventors
- 👤 Scott K. Reynolds
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:25
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/32; H03D; H03D7/00; H03D7/14; H03D7/1425; H03D7/1433; H03D7/145; H03D7/1491; H03D7/16; H03D7/165; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/4508; H03F3/45085; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/26; H04B1/28; H03D2200/00; H03D2200/0001; H03D2200/0023; H03D2200/0025; H03F2200/00; H03F2200/372; H03F2203/00; H03F2203/45; H03F2203/45306; H03F2203/45386; H03F2203/45492; H03F2203/45702; H03F2203/45704
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
56 words
A demodulator comprising: an input arrangement which accepts an input signal; an active balun circuit which amplifies the input signal and converts the input signal to differential form; at least one mixer; said active balun circuit being adapted to drive said at least one mixer; said active balun circuit comprising an asymmetrical negative shunt feedback arrangement.
Claim 2
Dependent Claim
56 words
A demodulator comprising: an input arrangement which accepts an input signal; an active balun circuit which amplifies the input signal and converts the input signal to differential form; at least one mixer; said active balun circuit being adapted to drive said at least one mixer; said active balun circuit comprising an asymmetrical negative shunt feedback arrangement.
Claim 3
Dependent Claim
26 words
The demodulator according to claim 1 , wherein said asymmetrical negative shunt feedback arrangement is adapted to apply variable gain in said at least one mixer.
Claim 4
Dependent Claim
21 words
The demodulator according to claim 1 , wherein said asymmetrical negative shunt feedback arrangement is adapted to provide stabilized input impedance.
Claim 5
Dependent Claim
25 words
The demodulator according to claim 1 , wherein said at least one mixer comprises two mixers, said two mixers being adapted to provide differential outputs.
Claim 6
Dependent Claim
22 words
The demodulator according to claim 1 , wherein said asymmetrical negative shunt feedback arrangement comprises a resistor and a capacitor in series.
Claim 7
Dependent Claim
32 words
The demodulator according to claim 1 , wherein said active balun circuit further comprises: a transistor; wherein said asymmetrical negative shunt feedback arrangement connects between the collector and base of said transistor.
Claim 8
Dependent Claim
32 words
The demodulator according to claim 1 , wherein said active balun circuit further comprises: an inverting output; wherein said asymmetrical negative shunt feedback arrangement interconnects said input arrangement with said inverting output.
Claim 9
Dependent Claim
41 words
The demodulator according to claim 7 , wherein said active balun circuit further comprises: a transistor; wherein said asymmetrical negative shunt feedback arrangement connects between the collector and base of said transistor in interconnecting said input arrangement with said inverting output.
Claim 10
Dependent Claim
33 words
The demodulator according to claim 7 , wherein said active balun circuit further comprises: a non-inverting output; and a compensating arrangement adapted to ensure approximately equal loading on said inverting and non-inverting outputs.
Claim 11
Dependent Claim
37 words
The demodulator according to claim 9 , wherein said compensating arrangement comprises an additional resistor and an additional capacitor in series, said additional resistor and additional capacitor in series being connected between said non-inverting input and ground.
Claim 12
Dependent Claim
43 words
The demodulator according to claim 7 , wherein said active balun circuit further comprises: a non-inverting output; said negative shunt feedback arrangement being adapted to reduce the amplitude of said inverting output more than a reduction in the amplitude of said non-inverting output.
Claim 13
Dependent Claim
50 words
The demodulator according to claim 1 , wherein said active balun circuit further comprises: an inverting output; a non-inverting output; and a first load tuning arrangement connected between said inverting output and power supply voltage; and a second load tuning arrangement connected between said non-inverting output and power supply voltage.
Claim 14
Dependent Claim
48 words
The demodulator according to claim 1 , wherein said active balun circuit further comprises: an inverting output; a non-inverting output; and a first load tuning arrangement connected between said inverting output and power supply voltage; and a second load tuning arrangement connected between said non-inverting output and ground.
Claim 15
Dependent Claim
19 words
The demodulator according to claim 1 , whereby overall distortion is reduced via said asymmetrical negative shunt feedback arrangement.
Claim 16
Dependent Claim
24 words
The demodulator according to claim 1 , wherein said demodulator is adapted for incorporation into a radio-frequency front end of a cellular telephone handset.
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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) | 2009-04-24 | 2009-10-24 | 2010-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2013-04-24 | 2013-10-24 | 2014-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2017-04-24 | 2017-10-24 | 2018-04-25 | $7700.00 | Window Closed / Lapsed |