US4759036A
Expired / Lapsed
US
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Decision-directed control circuit
Assignee: AT&T Inc
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Filing: 1987-03-02
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Granted: 1988-07-19
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Expires: 2007-03-02
Abstract
Abstract An improved decision-directed control circuit is disclosed which supplies adjustments to adaptive circuitry in a communications system. The improvement is achieved by only supplying adjustments when there is a high probability that the adjustment is correct. In the disclosed embodiments, this high probability equates, at a minimum, to times when the adaptive circuit output has an amplitude which lies outside of a range extending from the largest to the smallest value of the digital signal. This adjustment approach can be used to adjust a variety of adaptive circuits including transversal equalizers, timing recovery circuits, cross-polarization cancellers and carrier recovery circuits.
Inventors
- 👤 Martin H. Meyers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:31
CPC Classifications
H; H04; H04L; H04L1/00; H04L7/00; H04L7/0054; H04L7/0062; H04B; H04B7/00; H04B7/002; H04L25/00; H04L25/02; H04L25/03; H04L25/03006; H04L25/03012; H04L25/03019; H04L25/03038; H04L25/06; H04L25/20; H04L27/00; H04L27/02; H04L27/06; H04L27/066; H04L27/32; H04L27/34; H04L27/38; H04L7/0079; H04L7/0083
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
139 words
Decision-directed control apparatus for use in a communications signal receiver wherein each received signal conveys information on a plurality of discrete signal levels, said apparatus comprising adjustable means for processing each received signal to form an associated first output signal; means for determining when the amplitude of each first output signal in a predetermined group, comprising at least one preselected first output signal, lies outside of a range extending from a largest to a smallest of said signal levels; and means responsive to said determining means for supplying adjustments to said processing means if the amplitude of each first output signal in said group lies outside of said range and supplying no adjustments if the amplitude of each first output signal in said group lies within said range, said adjustments altering the signal processing provided by said processing means.
Claim 2
Dependent Claim
139 words
Decision-directed control apparatus for use in a communications signal receiver wherein each received signal conveys information on a plurality of discrete signal levels, said apparatus comprising adjustable means for processing each received signal to form an associated first output signal; means for determining when the amplitude of each first output signal in a predetermined group, comprising at least one preselected first output signal, lies outside of a range extending from a largest to a smallest of said signal levels; and means responsive to said determining means for supplying adjustments to said processing means if the amplitude of each first output signal in said group lies outside of said range and supplying no adjustments if the amplitude of each first output signal in said group lies within said range, said adjustments altering the signal processing provided by said processing means.
Claim 3
Dependent Claim
37 words
The apparatus of claim 1 wherein said determining means determines when the amplitude of each first output signal in said group lies outside an associated subset of said range and supplies this determination to said supplying means.
Claim 4
Dependent Claim
48 words
The apparatus of claim 2 wherein said supplying means supplies adjustments if the amplitude of each first output signal in said group lies outside of said range at first times and the amplitude of each first output signal in said group lies outside said subset at second times.
Claim 5
Dependent Claim
20 words
The apparatus of claim 1 wherein said supplying means supplies adjustments formed in accordance with a least mean square algorithm.
Claim 6
Dependent Claim
19 words
The apparatus of claim 1 wherein said supplying means supplies adjustments formed in accordance with a zero forcing algorithm.
Claim 7
Dependent Claim
23 words
The apparatus of claim 1 wherein said processing means delivers a second output signal associated with each received signal to said determining means.
Claim 8
Dependent Claim
45 words
The apparatus of claim 6 wherein said determining means determines when the amplitude of each second output signal in said predetermined group, comprising at least one second output signal, lies outside an associated subset of said range and supplies this determination to said supplying means.
Claim 9
Dependent Claim
53 words
The apparatus of claim 7 wherein said supplying means supplies adjustments to said processing means if the amplitude of each first output signal in said predetermined group lies outside said range at first times and the amplitude of each second output signal in said predetermined group lies outside said subset at second times.
Claim 10
Dependent Claim
22 words
The apparatus of claim 1 wherein said processing means includes a transversal equalizer which is supplied with adjustments by said supplying means.
Claim 11
Dependent Claim
23 words
The apparatus of claim 1 wherein said processing means includes a cross polarization canceller which is supplied with adjustments by said supplying means.
Claim 12
Dependent Claim
23 words
The apparatus of claim 1 wherein said processing means includes a timing recovery circuit which is supplied with adjustments by said supplying means.
Claim 13
Dependent Claim
23 words
The apparatus of claim 1 wherein said processing means includes a carrier recovery circuit which is supplied with adjustments by said supplying means.
Claim 14
Dependent Claim
20 words
The apparatus of claim 1 wherein each first output signal in said predetermined group varies with the signal processing adjustments.
Claim 15
Dependent Claim
20 words
The apparatus of claim 7 wherein each second output signal in said predetermined group varies with the signal processing adjustments.
Claim 16
Independent Claim
134 words
A method of adjusting decision-directed apparatus for use in a communications signal receiver wherein each received signal coveys information on a plurality of discrete signal levels, said method comprising the steps of processing each received signal to form an associated first output signal; determining when the amplitude of each first output signal in a predetermined group, comprising at least one first output signal, lies outside of a range extending from a largest to a smallest of said signal levels; and supplying adjustments which alter the processing provided to said received signal by said processing step if the amplitude of each first output signal in said group lies outside of said range and supplying no adjustments to said processing step if the amplitude of each first output signal in said group lies within said range.
Claim 17
Independent Claim
134 words
A method of adjusting decision-directed apparatus for use in a communications signal receiver wherein each received signal coveys information on a plurality of discrete signal levels, said method comprising the steps of processing each received signal to form an associated first output signal; determining when the amplitude of each first output signal in a predetermined group, comprising at least one first output signal, lies outside of a range extending from a largest to a smallest of said signal levels; and supplying adjustments which alter the processing provided to said received signal by said processing step if the amplitude of each first output signal in said group lies outside of said range and supplying no adjustments to said processing step if the amplitude of each first output signal in said group lies within said range.
Claim 18
Dependent Claim
38 words
The method of claim 15 further comprising the steps of determining when the amplitude of each first output signal in said group lies outside an associated subset of said range and supplying this determination to said supplying step.
Claim 19
Dependent Claim
62 words
The method of claim 16 wherein said supplying step supplies adjustments which alter the processing provided to said received signal by said processing step if the amplitude of each first output signal in said group lies outside of said range at first times and the amplitude of each first output second in said group lies outside of said subset at second times.
Claim 20
Dependent Claim
20 words
The method of claim 15 wherein said supplying step supplies adjustments formed in accordance with a least mean square algorithm.
Claim 21
Dependent Claim
19 words
The method of claim 15 wherein said supplying step supplies adjustments formed in accordance with a zero forcing algorithm.
Claim 22
Dependent Claim
23 words
The method of claim 15 wherein said processing step provides a second output siganl associated with each received signal to said determining step.
Claim 23
Dependent Claim
45 words
The method of claim 20 wherein said determining step determines when the amplitude of each second output signal in said predetermined group, comprising at least one second output signal, lies outside an associated subset of said range and supplies this determination to said supplying step.
Claim 24
Dependent Claim
62 words
The method of claim 21 wherein said supplying step supplies adjustments which alter the processing provided to said received signal by said processing step if the amplitude of each first output signal in said predetermined group lies outside said range at first times and the amplitude of each second output signal in said predetermined group lies outside said subset at second times.
Claim 25
Dependent Claim
25 words
The method of claim 15 wherein said processing of said received signal utilizes a transversal equalizer which is supplied with adjustments by said supplying step.
Claim 26
Dependent Claim
26 words
The method of claim 15 wherein said processing of said received signal includes a cross polarization canceller which is supplied with adjustments by said supplying step.
Claim 27
Dependent Claim
26 words
The method of claim 15 wherein said processing of said received signal includes a timing recovery circuit which is supplied with adjustments by said supplying step.
Claim 28
Dependent Claim
26 words
The method of claim 15 wherein said processing of said received signal includes a carrier recovery circuit which is supplied with adjsutments by said supplying step.
Claim 29
Dependent Claim
23 words
The method of claim 15 wherein each first output signal in said predetermined group varies with the adjustments provided to said processing step.
Claim 30
Dependent Claim
23 words
The method of claim 21 wherein each second output signal in said predetermined group varies with the adjustments provided to said processing step.
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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) | 1991-07-19 | 1992-01-18 | 1992-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-19 | 1996-01-18 | 1996-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-19 | 2000-01-18 | 2000-07-19 | $7700.00 | Window Closed / Lapsed |