On coding and decoding for high-order partial response systems

Author

Umemoto, Masuo

Author_Institution

Central Res. Lab., Hitachi Ltd., Tokyo, Japan

Volume

34

Issue

1

fYear

1998

fDate

1/1/1998 12:00:00 AM

Firstpage

80

Lastpage

84

Abstract

High-data-rate signal processing for hard disk drives is discussed. A recording channel is equalized as a partial response (PR) (1+D)(1-D³), where D is a delay operator. Furthermore, 1/(1+D) pre-coding scheme is used, and the resulting response is given as (1-D³), which achieves three-bit interleaving. The working speed of each Viterbi detector in interleaving PR channels is reduced to one third of the original bit-frequency. The performance of the reduced two-state Viterbi detector in the interleaving PR channel is compared with the conventional two-state Viterbi detector of the PR4 system. As a result, the proposed system improves the signal-to-noise ratio by about 3.0 db compared with the baseline PR4 maximum system. Finally, it is shown that the Error Coding (ECC) scheme for the interleaving needs a reversed hierarchy of ECC and channel coding

Keywords

Viterbi detection; channel coding; decoding; error correction codes; hard discs; interleaved codes; magnetic recording noise; partial response channels; PR channel; PR4 system; channel coding; coding; decoding; delay operator; equalization; error coding; hard disk drive; high-order partial response system; pre-coding; recording channel; signal processing; signal-to-noise ratio; three-bit interleaving; two-state Viterbi detector; Decoding; Delay; Detectors; Disk recording; Error correction codes; Hard disks; Interleaved codes; Signal processing; Signal to noise ratio; Viterbi algorithm;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.663453

Filename

663453