公开(公告)号：JP2001101020A

公开(公告)日：2001-04-13

申请号：JP27221499

申请日：1999-09-27

Applicant: IBM

Inventor： KATO KATSUHIKO

IPC: G06F11/10 ,  G11B20/18 ,  H03M13/09

Abstract: PROBLEM TO BE SOLVED: To quickly attain disappearance correction by minimizing the increase of the scale of hardware. SOLUTION: In operating disappearance correction, a disappearance locator is generated by an MPU 6, and error data are calculated, based on a reading code word and disappearing position data by an error calculating circuit 21, and the error data successively outputted from the error calculating circuit 21 are successively held in an MPU 6, and the error data are successively transferred from an error data transferring circuit 23 through a CRC control circuit 24 to CRC calculating circuits 25a, 25b, 25c, and 25d, and a CRC syndrome is calculated based on the reading code word and the error data by the CRC calculating circuits 25a, 25b, 25c, and 25d, and whether or not all the error data are correct is judged based on the CRC syndrome by a CRC discrimination circuit 26, and when all the error data are corrected, the code word is corrected according to the held error data by the MPU 6.

公开(公告)号：JP2003346432A

公开(公告)日：2003-12-05

申请号：JP2002148290

申请日：2002-05-22

Applicant: Internatl Business Mach Corp ,  インターナショナル・ビジネス・マシーンズ・コーポレーション

Inventor： KATO KATSUHIKO ,  KURODA TAKASHI ,  UCHIIKE HIROSHI ,  TAKASE YASUHIRO

IPC: G06F11/10 ,  G11B20/18 ,  H03M13/15

CPC classification number: G11B20/1833 ,  G11B2220/2516

Abstract: PROBLEM TO BE SOLVED: To attain the correction of a bigger error without increasing the overhead of a code.
SOLUTION: The correlation is generated among sectors 0-2 by making the exclusive OR (XOR) of user data (sector) 0, user data (sector) 1 and user data (sector) 2 to obtain virtual user data, and by producing C2 having the error correcting ability larger than that of C1 to the virtual user data, the error correction becomes available by C2 even though the error is uncorrectable (Uncorrectable) by C1.
COPYRIGHT: (C)2004,JPO

Abstract translation: 要解决的问题：在不增加代码开销的情况下获得较大误差的校正。 解决方案：通过使用户数据（扇区）0，用户数据（扇区）1和用户数据（扇区）2的异或（XOR）0获得虚拟用户数据，在扇区0-2中生成相关性，以及 通过产生具有大于C1的纠错能力的C2到虚拟用户数据，即使错误是C1不可校正（不可校正），也可通过C2获得纠错。 版权所有（C）2004，JPO

公开(公告)号：JP2003141822A

公开(公告)日：2003-05-16

申请号：JP2001325696

申请日：2001-10-23

Applicant: IBM

Inventor： KATO KATSUHIKO ,  FUKUSHIMA YUKIO ,  UEDA TETSUO ,  NAKAGAWA YUZO ,  SHIMONO EMI ,  KURODA TAKASHI ,  KOBAYASHI SHUNSUKE ,  TAMURA TETSUYA ,  SAI FUMINORI

IPC: G06F11/08 ,  G06F3/06 ,  G11B20/10 ,  G11B20/18 ,  H03M13/43

Abstract: PROBLEM TO BE SOLVED: To contribute to the generation of correct read data by increasing the probability of error corrections. SOLUTION: Reading about the same sector is performed multiple times, the majority is taken in the same address (Address), and the most frequent value is considered to be a genuine data value. For example, in an address 00, '00' is treated as a genuine data value.

公开(公告)号：JP2001044853A

公开(公告)日：2001-02-16

申请号：JP18156299

申请日：1999-06-28

Applicant: IBM

Inventor： KATO KATSUHIKO ,  NAKAMURA AKIO ,  TAMURA TETSUYA

IPC: G06F11/10 ,  G11B20/18 ,  H03M13/15

Abstract: PROBLEM TO BE SOLVED: To provide a chain search circuit that shourtens the time required for chain search without having to increase the number of gates of a multiplication result storage circuit, when conducting pipeline processing for quickening chain search. SOLUTION: A chain search circuit 55 is provided with flip-flop circuits(FF) 101a to 101c, that are provided corresponding to each term of an error location polynomial, store each coefficient of the error location polynomial for an initial value and store a multiplication result of multiplying an element of a Galois field with each coefficient, high-order fixed multipliers 103a to 103c that multiply the powers (αn) of the highest order αrespectively in parallel corresponding to the flip-flop circuits(FF) 101a to 101c, and low order fixed multipliers 104a to 104c that respectively multiply the powers (αn-1) of the lower order α, and the flip-flop circuits (FF) 101a to 101c latch only the result of products of the high-order fixed multipliers 103a to 103c that multiply the powers (αn) of the highest order α.

公开(公告)号：JP2000057707A

公开(公告)日：2000-02-25

申请号：JP23081898

申请日：1998-08-17

Applicant: IBM

Inventor： KATO KATSUHIKO ,  KURODA TAKASHI ,  SAKAI TATSUYA

IPC: G11B20/18 ,  H03M13/23

Abstract: PROBLEM TO BE SOLVED: To provide a reproduction control apparatus, a reproduction control method and a disk drive device, in which the reliability for data reproduction is enhanced. SOLUTION: When an error contained in reproduced data from maximum likelihood decoding section 24 is equal to or less than the error correction ability of an error correction system 10, data for which the error correction has been performed by holding, in a register 12, an error position and pattern determined by an error calculating section 11 are sequentially output. When an error exceeds the error correction cap ability, the data is re-read, and an output of a byte counter 7, which indicates the position of the reproduced data when a viterbi decoder error signal has been supplied, is supplied to the register 12, and the error correction is performed in accordance with the thus-supplied error position as well as the error pattern determined by the error calculating section 11.