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US 8,970,981 B2Granted
Hardware support of servo format with two preamble fields
AssigneeLSI Corporation
InventorsXun Zhang, Haitao Xia, Dahua Qin
Life of this patent
Estimating the term…
Abstract
A hard disk drive uses a second, reference burst field in a preamble to estimate burst phase and burst magnitude. Such estimations are used for position error signal integration and repeatable runout correction. Gain error is also derived from such estimations. Information contained in a preamble field is used in conjunction with the reference burst phase estimation to synchronize servo address marks.
Claims20
A hard disk drive comprising:
- a processor;
- memory connected to the processor;
- a storage element connected to the processor;
- and
- computer executable program code configured to execute on the processor,
- wherein the computer executable program code is configured to:
- receive a data stream from the storage element, the data stream comprising:
- a preamble comprising at least a first field and a second field, the second field comprising a reference burst, the preamble having a resolution for maintaining a first pattern at a first rate, the reference burst having a resolution for maintaining a second pattern at a second rate;
- and
- a position error signal burst wherein the position error signal burst and the reference burst comprise a common frequency;
- calculate a burst phase estimation based on the reference burst;
- and
- calculate a burst magnitude estimation based on the reference burst.
10 more elements
A method comprising:
- receiving a data stream, the data stream comprising:
- a preamble comprising at least a first field and a second field, the second field comprising a reference burst, the preamble having a resolution for maintaining a first pattern at a first rate, the reference burst having a resolution for maintaining a second pattern at a second rate;
- and
- a position error signal burst wherein the position error signal burst and the reference burst comprise a common frequency;
- calculating a burst phase estimation based on the reference burst;
- calculating a burst magnitude estimation based on the reference burst;
- and
- calculating a position error signal burst integration based on the burst phase estimation.
5 more elements
A computer apparatus comprising:
- a processor;
- and
- memory connected to the processor,
- wherein the processor is configured to:
- receive a data stream, the data stream comprising:
- a preamble comprising at least a first field and a second field, the second field comprising a reference burst, the preamble having a resolution for maintaining a first pattern at a first rate, the reference burst having a resolution for maintaining a second pattern at a second rate;
- and
- a position error signal burst wherein the position error signal burst and the reference burst comprise a common frequency;
- calculate a burst phase estimation based on the reference burst;
- calculate a burst magnitude estimation based on the reference burst;
- and
- calculating a position error signal burst integration based on the burst phase estimation.
9 more elements
Dependencies are inferred from the claim text.