US5243605A
Expired / Lapsed
US
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Modified viterbi detector with run-length code constraint
Assignee: Storage Technology Corp
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Filing: 1991-07-11
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Granted: 1993-09-07
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Expires: 2011-07-11
Abstract
Abstract A digital data decoder is provided that combines Viterbi algorithms and a run-length code constraint. The combined Viterbi detection and code constraint does not limit the bits that can be analyzed in determining the binary state of the bit currently being detected. The logic associated with the code constraint is not enabled unless actual data is being decoded.
Inventors
- 👤 Brahim Lekmine
- 👤 Donald L. Millican
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:06
CPC Classifications
H; H03; H03M; H03M13/00; H03M13/37; H03M13/39; H03M13/41; G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1423; G11B20/1426; G11B20/18; G11B20/1833
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
134 words
A method for decoding data using a combination of Viterbi detection and a run-length code constraint, comprising: obtaining data comprising a number of bits from a storage device; and determining a binary state of a first bit using a combination of Viterbi detection means and run-length code constraint means having a code constraint defined as (d,k), where k is a predetermined value equal to the maximum number of bits of a first bindary state that are found in a data record between two consecutive bits of the other binary state d, said step of determining including using a second bit to determine said binary state of said first bit, with said second bit being obtained after said first bit and in which said second bit occurs greater than k bits after said first bit.
Claim 2
Independent Claim
134 words
A method for decoding data using a combination of Viterbi detection and a run-length code constraint, comprising: obtaining data comprising a number of bits from a storage device; and determining a binary state of a first bit using a combination of Viterbi detection means and run-length code constraint means having a code constraint defined as (d,k), where k is a predetermined value equal to the maximum number of bits of a first bindary state that are found in a data record between two consecutive bits of the other binary state d, said step of determining including using a second bit to determine said binary state of said first bit, with said second bit being obtained after said first bit and in which said second bit occurs greater than k bits after said first bit.
Claim 3
Independent Claim
120 words
A method for decoding data using a combination of Viterbi detection and a run-length code constraint, comprising: obtaining data comprising a number of bits from a storage device; and determining a binary state of a first bit using a combination of Viterbi detection means and run-length code constraint means having a code constraint defined as (d,k), where k is a predetermined value equal to the maximum number of bits of a first binary state that are formed in a data record between two consecutive bits of the other binary state d, said step of determining including determining a binary state of another bit, different from said first bit, during said step of determining said binary state of said first bit.
Claim 4
Independent Claim
120 words
A method for decoding data using a combination of Viterbi detection and a run-length code constraint, comprising: obtaining data comprising a number of bits from a storage device; and determining a binary state of a first bit using a combination of Viterbi detection means and run-length code constraint means having a code constraint defined as (d,k), where k is a predetermined value equal to the maximum number of bits of a first binary state that are formed in a data record between two consecutive bits of the other binary state d, said step of determining including determining a binary state of another bit, different from said first bit, during said step of determining said binary state of said first bit.
Claim 5
Dependent Claim
26 words
A method, as claimed in claim 2, wherein: said step of determining includes using a number of bits less than k in determining said another bit.
Claim 6
Dependent Claim
65 words
A method, as claimed in claim 1, wherein: said values of (d,k) correspond to (0,3) and said number of bits obtained equals at least third enough fifth bits, with each of said third through fifth bits being consecutively obtained after said first and second bits, and wherein said step of determining includes using said fifth bit in determining said binary state of said first bit.
Claim 7
Dependent Claim
40 words
A method, as claimed in claim 1, wherein said step of determining includes enabling said run-length code constraint means when determining said binary state of said first bit and not enabling said run-length code constraint means when obtaining non-data information.
Claim 8
Dependent Claim
29 words
A method, as claimed in claim 1, wherein: said step of determining includes using a tracking threshold that relates to a binary state of at least said first bit.
Claim 9
Dependent Claim
49 words
A method, as claimed in claim 1, wherein: said step of determining includes determining the difference between a value relating to said first bit and a value relating to a bit obtained after said first bit and using said difference in determining said binary state of said first bit.
Claim 10
Dependent Claim
24 words
A method, as claimed in claim 7, wherein said step of determining includes determining a relationship associated with said difference and a predetermined magnitude.
Claim 11
Dependent Claim
26 words
A method, as claimed in claim 8, wherein: said predetermined magnitude equals zero and said step of determining a relationship includes comparing said difference with zero.
Claim 12
Dependent Claim
29 words
A method, as claimed in claim 7, wherein: said step of determining includes inputting a tracking threshold and determining a relationship associated with said difference and said tracking threshold.
Claim 13
Dependent Claim
33 words
A method, as claimed in claim 10, wherein said step of determining a relationship includes comparing said difference with said tracking threshold and said step of determining includes comparing said difference with zero.
Claim 14
Dependent Claim
44 words
A method, as claimed in claim 1, wherein: said step of determining includes determining the signs of the differences between a value of said first bit and a value of each of a number of consecutive bits that are obtained after said first bit.
Claim 15
Dependent Claim
37 words
A method, as claimed in claim 1, wherein: said step of determining includes determining a binary state of a second bit, which is obtained after said first bit, before determining said binary state of said first bit.
Claim 16
Dependent Claim
61 words
A method, as claimed in claim 1, wherein said step of obtaining includes: reading said data and generating an analog signal representative thereof; and converting said analog signal to a digital signal, wherein said step of determining is conducted using a digital first bit and a number of consecutively read digital bits in determining said binary state of said first bit.
Claim 17
Independent Claim
124 words
An apparatus for decoding data using a combination of Viterbi detection and run-length code constraint, comprising: first means for providing a number of data bits; and a combination of Viterbi detection means and run-length limited code means responsive to said first means for determining a binary state of a first bit of said number of bits, said combination having a urn-length code constraint defined as (d,k), where k is a predetermined value equal to the maximum number of bits of a first binary state that are found in a data record between two consecutive bits of the other binary state d, said combination determining said first bit binary state by using a second bit that occurs greater than k bits after said first bit.
Claim 18
Independent Claim
124 words
An apparatus for decoding data using a combination of Viterbi detection and run-length code constraint, comprising: first means for providing a number of data bits; and a combination of Viterbi detection means and run-length limited code means responsive to said first means for determining a binary state of a first bit of said number of bits, said combination having a urn-length code constraint defined as (d,k), where k is a predetermined value equal to the maximum number of bits of a first binary state that are found in a data record between two consecutive bits of the other binary state d, said combination determining said first bit binary state by using a second bit that occurs greater than k bits after said first bit.
Claim 19
Dependent Claim
38 words
An apparatus, as claimed in claim 15, wherein: said combination includes magnitude and sign determining circuitry means responsive to said first means for determining a value relating to a difference between said first bit and said second bit.
Claim 20
Dependent Claim
42 words
An apparatus, as claimed in claim 16, wherein: said magnitude and sign determining circuitry means includes means for determining a polarity relating to said first bit and each of third and fourth bits that are provided after said first and second bits.
Claim 21
Dependent Claim
21 words
An apparatus, as claimed in claim 15, wherein: said first means includes means for inputting a tracking threshold to said combination.
Claim 22
Dependent Claim
33 words
An apparatus, as claimed in claim 15, further including: a control unit for outputting an enabling signal to said combination when reading data and not outputting said enabling signal when reading non-data information.
Claim 23
Dependent Claim
21 words
An apparatus, as claimed in claim 15, wherein: said first means includes a storage device for storing data represented by bits.
Claim 24
Dependent Claim
15 words
An apparatus, as claimed in claim 20, wherein: said storage device includes a magnetic medium.
Claim 25
Dependent Claim
21 words
An apparatus, as claimed in claim 21, wherein: said first means includes magnetic means for reading data from said magnetic medium.
Claim 26
Dependent Claim
23 words
An apparatus, as claimed in claim 15, wherein: said first means includes means for converting an analog read signal to a digital signal.
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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) | 1996-09-06 | 1997-03-08 | 1997-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-06 | 2001-03-08 | 2001-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-06 | 2005-03-08 | 2005-09-07 | $7700.00 | Window Closed / Lapsed |