US5134631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital gain controller
Assignee: Unisys Corp
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Filing: 1990-07-26
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Granted: 1992-07-28
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Expires: 2010-07-26
Abstract
Abstract A novel programmable digital gain controller is provided for the automatic gain control loop of a communications receiver. The digital gain controller comprises a pair of digital detectors coupled to the real and imaginary components of a data stream for providing digital data magnitude output signals which are coupled to an adder whose output is coupled to a first input of a comparator having a second input coupled to a predetermined reference level command. The output of the comparator generates a digital error signal which is coupled to the input of a programmable gain accumulator having a second input proportional gain command so as to provide at the output of the programmable gain accumulator a digital gain command which may be coupled to a variable gain controlled amplifier which is connected in the input data stream of the channel of a communications receiver to provide a predetermine amplifier output level.
Inventors
- 👤 Samuel C. Kingston
- 👤 Steven T. Barham
- 👤 Harold L. Simonsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:10
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3052; H04; H04K; H04K3/00; H04K3/20; H04K3/22; H04K3/224
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
150 words
A programmable digital gain controller of the type employed in the data stream of a channel of a digital communications receiver, comprising: amplifier means connected in the data stream of a receiver channel, digital detector means connected to said data stream for providing digital data magnitude output signals, digital comparator means coupled to said data magnitude signals, reference level signals coupled to said digital comparator means for providing gain error output signals from said comparator means, and digital programmable gain accumulator means coupled to said gain error output signals for providing digital gain commands which are coupled in a feedback loop to said amplifier means to provide a predetermined amplifier means output level, said digital programmable gain accumulator means having a proportional gain command level input for setting gain levels and having an overriding gain control input for overriding said digital gain command before being coupled to said amplifier means.
Claim 2
Dependent Claim
150 words
A programmable digital gain controller of the type employed in the data stream of a channel of a digital communications receiver, comprising: amplifier means connected in the data stream of a receiver channel, digital detector means connected to said data stream for providing digital data magnitude output signals, digital comparator means coupled to said data magnitude signals, reference level signals coupled to said digital comparator means for providing gain error output signals from said comparator means, and digital programmable gain accumulator means coupled to said gain error output signals for providing digital gain commands which are coupled in a feedback loop to said amplifier means to provide a predetermined amplifier means output level, said digital programmable gain accumulator means having a proportional gain command level input for setting gain levels and having an overriding gain control input for overriding said digital gain command before being coupled to said amplifier means.
Claim 3
Dependent Claim
54 words
A programmable digital gain controller as set forth in claim 1 wherein said data stream comprises a real and an imaginary component each being coupled to said digital detector means, adder means coupled to the output of said digital detector means for providing said digital data magnitude signals coupled to said digital comparator means.
Claim 4
Dependent Claim
32 words
A programmable digital gain controller as set forth in claim 2 wherein said digital detector means comprises individual magnitude detectors coupled to said real and said imaginary components of said data stream.
Claim 5
Dependent Claim
34 words
A programmable digital gain controller as set forth in claim 3 wherein said individual magnitude detectors comprise absolute value detectors connected in series in said real and said imaginary components of said data stream.
Claim 6
Dependent Claim
35 words
A programmable digital gain controller as set forth in claim 3 wherein said individual magnitude detector means comprises square law detectors coupled in series and said real and said imaginary components of said data stream.
Claim 7
Dependent Claim
19 words
A programmable digital gain controller as set forth in claim 1 wherein said comparator means comprises a digital subtractor.
Claim 8
Dependent Claim
20 words
A programmable digital gain controller as set forth in claim 2 wherein said adder means comprises a digital summing circuit.
Claim 9
Dependent Claim
52 words
A programmable digital gain controller as set forth in claim 1 which further includes saturation control means coupled to said programmable gain accumulator means overriding gain control input and to said data stream for providing overriding gain control signal to said programmable gain accumulation means when the data stream signals are saturated.
Claim 10
Dependent Claim
25 words
A programmable digital gain controller as set forth in claim 8 wherein said saturation control means comprises a saturation detector coupled to said data stream.
Claim 11
Dependent Claim
29 words
A programmable digital gain controller as set forth in claim 9 wherein said saturation control means further comprises an up/down counter coupled to the output of said saturation detector.
Claim 12
Dependent Claim
45 words
A programmable digital gain controller as set forth in claim 10 wherein said saturation control means further comprises a multiplexor coupled to the carry output of said up/down counter and having an error signal output coupled to the input of said programmable gain accumulator means.
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) | 1995-07-28 | 1996-01-27 | 1996-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-28 | 2000-01-27 | 2000-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-28 | 2004-01-27 | 2004-07-28 | $7700.00 | Window Closed / Lapsed |