Precise Write-Time Compensation for Nonlinear Transition Shift in Magnetic Tape Recording Using a d=1 RLL Code

Toshihiro UEHARA  Keigo MAJIMA  Shoichiro OGAWA  Junji NUMAZAWA  

IEICE TRANSACTIONS on Electronics   Vol.E82-C   No.12   pp.2234-2240
Publication Date: 1999/12/25
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Issue on Information Storage Technologies for the 21st Century)
write-time compensation,  nonlinear transition shift,  VCR,  RLL code,  

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We propose precise write-time compensation for nonlinear transition shift in magnetic tape recording using d=1 runlength-limited (RLL) code as a channel modulation. In this write-time compensation approach, the write current transitions having a transition within 3 bits earlier are shifted so as to minimize the transition shift of the readback signal. First, we precisely measured the nonlinear transition shift using a VCR. Next, based on this measurement, we simulated the effects of the write-time compensation, verifying them in recording experiments with a VCR. The results show that when the optimum read equalization is applied to the readback signal, this write-time compensation approach increases the eye height and eye width while improving the byte error rate by about two orders.