US5455813A
Expired / Lapsed
US
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Digital signal reproducing apparatus
Assignee: Pioneer Corp
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Filing: 1993-11-05
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Granted: 1995-10-03
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Expires: 2013-11-05
Abstract
Abstract A digital signal reproducing apparatus reproduces a digital signal with a sampling clock of a high precision that is synchronized with a phase of a read signal. A predetermined sample value series are detected from the sampling data obtained by A/D converting the read signal. Then the mean value of the sample values in the sample value series is obtained. The apparatus produces a sampling clock which is phase corrected on the basis of the mean value.
Inventors
- 👤 Hideki Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:21
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/10009; G11B20/10037; G11B20/14; G11B20/1403
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
124 words
A digital signal reproducing apparatus for reproducing a digital signal from a read signal that is read out from a recording medium on which the digital signal is recorded, comprising: an A/D converter for sequentially sampling said read signal by a sampling clock and obtaining a sample value series; a detector for detecting a predetermined sample value series in said sample value series; a mean value calculating circuit for obtaining a mean value of sample values of said predetermined sample value series; and a clock generator for generating said sampling clock whose phase is corrected by said mean value; wherein said detector is operative to detect whether a change in level between adjacent sample values of said sample value series exceeds an allowable limit.
Claim 2
Dependent Claim
124 words
A digital signal reproducing apparatus for reproducing a digital signal from a read signal that is read out from a recording medium on which the digital signal is recorded, comprising: an A/D converter for sequentially sampling said read signal by a sampling clock and obtaining a sample value series; a detector for detecting a predetermined sample value series in said sample value series; a mean value calculating circuit for obtaining a mean value of sample values of said predetermined sample value series; and a clock generator for generating said sampling clock whose phase is corrected by said mean value; wherein said detector is operative to detect whether a change in level between adjacent sample values of said sample value series exceeds an allowable limit.
Claim 3
Dependent Claim
44 words
An apparatus according to claim 1, wherein said detector is operative to detect the sample value series as said predetermined sample value series when a change in level between the adjacent sample values in said sample value series is larger than a predetermined value.
Claim 4
Dependent Claim
40 words
An apparatus according to claim 1, wherein said mean value calculating circuit is operative to obtain a symmetrical weighted mean for the sample values of said predetermined sample value series and sets said symmetrical weighted mean to said mean value.
Claim 5
Dependent Claim
43 words
The digital signal reproducing apparatus according to claim 2 wherein said mean value calculating circuit is operative to obtain a symmetrical weighted mean for the sample values of said predetermined sample value series and sets said symmetrical weighted mean to said mean value.
Claim 6
Dependent Claim
28 words
The digital signal reproducing apparatus according to claim 4, further comprising a polarity switching circuit responsive to said detector to assign a proper polarity to said means value.
References Cited (Backward Citations)
US4566091A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-10-02 | 1999-04-03 | 1999-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-02 | 2003-04-03 | 2003-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-02 | 2007-04-03 | 2007-10-03 | $7700.00 | Window Closed / Lapsed |