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A rate 4/6 (d=1, k=11) block-decodable runlength-limited code

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Abstract

A new rate 4/6 (d=1, k'=11) runlength-limited code which is well adapted to byte-oriented storage systems is presented. The new code has the virtue that it can be decoded on a block basis, i.e., without knowledge of previous or next codewords, and, therefore, it does not suffer from error propagation. This code is particularly attractive as many commercially available Reed-Solomon codes operate in GF(2<sup>8 </sup>)

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... One-dimensional (1D) run-length limited (RLL) code was previously proposed for magnetic and optical recording systems [4][5][6] to specify the minimum and maximum run-length of bit 1's that may occur in a recorded data sequence. In practice, the RLL code is normally defined by two parameters that are d and k, where the parameter d is used for controlling the highest transition frequency that means it can avoid the ISI effect, while the parameter k is used to ensure that the transition of the 978-1-7281-6486-1/20/$31.00 ©2020 IEEE recorded bit data has properly appeared, which can help the synchronization process to precisely recover the sampled data sequence [7]. As a consequence, the use of a 1D RLL code can efficiently improve the recording performance. ...
... However, in this work, the 1D RLL code is applied for an MHMT BPMR system, and we name our proposed coding technique as the rate-4/6 2D modulation code. Specifically, an encoded data sequence will be rearranged in the vertical direction, to avoid the severe ITI data patterns, instead of the traditional one that arranges a codeword in the horizontal direction [7]. ...
... Let us consider the rate-4/6 (d = 1, k = 11) block-decodable RLL code [7]. With this RLL code, 16 sourcewords are mapped by two groups of codewords. ...
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