公开(公告)号：GB2544586B

公开(公告)日：2020-04-01

申请号：GB201614813

申请日：2016-09-01

Applicant: IBM

Inventor： SIMEON FURRER ,  STEVEN ROSS BENTLEY ,  ROY DARON CIDECIYAN ,  KEISUKE TANAKA

IPC: G11B20/18 ,  G11B5/008

公开(公告)号：GB2562352A

公开(公告)日：2018-11-14

申请号：GB201803554

申请日：2016-11-29

Applicant: IBM

Inventor： ROBERT ALLEN HUTCHINS ,  STEVEN ROSS BENTLEY ,  KEISUKE TANAKA ,  ROY DARON CIDECIYAN

IPC: H03M13/29 ,  G11B20/18

Abstract: A system includes a controller and logic integrated with and/or executable by the controller. The logic is configured to perform iterative decoding on encoded data to obtain decoded data. At least three decoding operations are performed in the iterative decoding, with the decoding operations being selected from a group comprising:C1 decoding and C2 decoding. The logic is also configured to perform post-decoding error diagnostics on a first portion of the decoded data in response to not obtaining a valid product codeword in the first portion after the iterative decoding of the encoded data. Other systems, methods, and computer program products for producing post-decoding error signatures are also presented.

公开(公告)号：GB2545964B

公开(公告)日：2021-05-05

申请号：GB201618530

申请日：2016-11-03

Applicant: IBM

Inventor： KEISUKE TANAKA ,  STEVEN ROSS BENTLEY ,  SIMEON FURRER ,  ROY DARON CIDECIYAN

IPC: G11B20/18

Abstract: In one embodiment, a tape drive includes a magnetic head having a plurality of read sensors, each read sensor being configured to read data simultaneously. The tape drive also includes a controller and logic integrated with and/or executable by the controller. The logic is configured to receive encoded data read from a plurality of tracks of a magnetic tape medium simultaneously. The logic is also configured to perform priority-based decoding on the encoded data based on erasure coefficients associated with at least one codeword of the encoded data. In another embodiment, a controller-implemented method includes receiving encoded data read from a plurality of tracks of a magnetic tape medium simultaneously and performing priority-based decoding on the encoded data based on erasure coefficients associated with at least one codeword of the encoded data.

公开(公告)号：GB2545964A

公开(公告)日：2017-07-05

申请号：GB201618530

申请日：2016-11-03

Applicant: IBM

Inventor： KEISUKE TANAKA ,  STEVEN ROSS BENTLEY ,  SIMEON FURRER ,  ROY DARON CIDECIYAN

IPC: G11B20/18

Abstract: A tape drive includes a magnetic head having a plurality K of read sensors, each read sensor being configured to read data simultaneously. The tape drive also includes a controller and logic integrated with and/or executable by the controller. The logic is configured to receive encoded data read from a plurality of tracks of a magnetic tape medium simultaneously. The logic is also configured to perform priority-based decoding on the encoded data based on erasure coefficients associated with at least one codeword of the encoded data. Erasure pointers for C2 decoding may be enabled if, and only if, C1 codewords include a large number of byte errors. Each erasure pointer may have an erasure coefficient (wi fig. 6) indicating probability that the C2 decoder should treat the corresponding C1 bytes as erasures.

公开(公告)号：GB2562352B

公开(公告)日：2019-03-06

申请号：GB201803554

申请日：2016-11-29

Applicant: IBM

Inventor： ROBERT ALLEN HUTCHINS ,  STEVEN ROSS BENTLEY ,  KEISUKE TANAKA ,  ROY DARON CIDECIYAN

IPC: H03M13/29 ,  G11B20/18

Abstract: In one embodiment, a system includes a controller and logic integrated with and/or executable by the controller. The logic is configured to perform iterative decoding on encoded data to obtain decoded data. The logic is also configured to perform post-decoding error diagnostics on a first portion of the decoded data in response to not obtaining a valid product codeword in the first portion after the iterative decoding of the encoded data. Other systems, methods, and computer program products for producing post-decoding error signatures are presented in accordance with more embodiments.

公开(公告)号：GB2544586A

公开(公告)日：2017-05-24

申请号：GB201614813

申请日：2016-09-01

Applicant: IBM

Inventor： SIMEON FURRER ,  STEVEN ROSS BENTLEY ,  ROY DARON CIDECIYAN ,  KEISUKE TANAKA

IPC: G11B20/18 ,  G11B5/008

Abstract: A tape drive includes a magnetic head having a plurality of read sensors, each read sensor being configured to read data simultaneously, a controller, and logic integrated with and/or executable by the controller. The logic is configured to read, using the plurality of read sensors, encoded data from a plurality of tracks of a magnetic tape medium simultaneously. The logic is also configured to perform track-dependent erasure decoding on the encoded data based on detection of one or more time-varying signal quality issues associated with at least one of the plurality of tracks read simultaneously from the magnetic tape medium. The time varying signal quality may be determined based on reliability of detected bytes within C1 codewords or number of run-length limited (RLL) error detection flags per C1 codeword. C2 decoding on a plurality of erasure enabled C1 codewords may be performed with C2 error and erasure decoding. Erasure pointers may be inserted in place of each C1 codeword when a probability of byte errors in the C1 codeword exceeds a threshold.