Practical equalizer for a perpendicular magnetic disk

Author

Ishikawa, Kiyohiko ; Kishida, Masahiko ; Kamijo, Koji ; Taguchi, Ryo ; Okuda, Haruo ; Numazawa, Junji

Author_Institution

Sci. & Tech. Res. Labs., Japan Broadcasting Corp., Tokyo, Japan

Volume

38

Issue

6

fYear

2002

fDate

11/1/2002 12:00:00 AM

Firstpage

3684

Lastpage

3688

Abstract

We have developed a readback equalizer for a perpendicular magnetic disk with a commercial anisotropic magnetoresistive head for use with a PR4ML read channel with 8-9 coding. The transfer function of the perpendicular magnetic disk, derived by Fourier analysis, has a phase lag of 90° from that of the longitudinal magnetic disk. We defined the parameters of the equalizer by simulation. The equalized readback signal nearly satisfied Nyquist´s first criterion. Using resistor-capacitor circuits that correspond to the simulated function, we obtained a byte-error rate of below 10^-7. Comparing the effect of incorporating PR4 or PR1 as part of the equalizer, we observed that PR4 gave a lower bit-error rate than PR1. Thus, PR4 is an effective detection method for a perpendicular magnetic disk. It is suitable not only for longitudinal magnetic disks, but also for perpendicular magnetic disks.

Keywords

Fourier analysis; equalisers; magnetic disc storage; perpendicular magnetic recording; transfer functions; 8-9 coding; Fourier analysis; Nyquist criterion; PR4ML read channel; RC pseudodifferential circuit; anisotropic magnetoresistive head; byte error rate; perpendicular magnetic disk; phase lag; readback equalizer; transfer function; Anisotropic magnetoresistance; Bit error rate; Disk recording; Equalizers; Magnetic analysis; Magnetic anisotropy; Magnetic heads; Perpendicular magnetic anisotropy; Perpendicular magnetic recording; Transfer functions;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2002.804799

Filename

1158961