S/N of conventional EPRML by approximately 4 dB at a bit error rate of 10-6." />

Modified EEPRML with 16/17 (3;11) MTR Code and Cyclic Redundancy Check Code for High Density Magnetic Recording Channels

Seiichi MITA  Hideki SAWAGUCHI  Takushi NISHIYA  Naoya KOBAYASHI  

IEICE TRANSACTIONS on Electronics   Vol.E82-C   No.12   pp.2201-2208
Publication Date: 1999/12/25
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: INVITED PAPER (Special Issue on Information Storage Technologies for the 21st Century)
EPRML,  EEPRML,  MTR code,  Viterbi detector,  cyclic redundancy check code,  

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Three basic ideas for enhancing the performance of extended EPRML (EEPRML) are described in detail. The first is the modification of the EEPRML impulse response in order to minimize the bit error rate of read signals from magnetic recording channels. This modification can improve the signal to noise ratio (S/N) of conventional extended partial response maximum likelihood (EPRML) by approximately 1 dB. The second is the introduction of 16/17 (3;11) maximum transition run code (MTR). This code can completely eliminate error events of more than four consecutive bits from modified EEPRML error events, and reduce the probability of minimum distance error events occurring by one eighth. Finally, dominant error events such as {0e0}, {0ee0}, {0eee0}, and {0e00e0} before 16/17 (3,11) MTR decoding can be corrected by employing cyclic redundancy check code (CRCC) with soft decision decoding. The symbol "e" represents one bit error, namely, "1" to "0" or vice versa and "0" represents a correct bit. Total performance has been evaluated by computer simulations using an isolated waveform similar to actual read signals and additive white Gaussian noise. Consequently, it has been confirmed that modified EEPRML with 16/17 (3;11) MTR code and CRCC can improve the S/N of conventional EPRML by approximately 4 dB at a bit error rate of 10-6.