On Bi-Modal Constrained Coding

Ron M. Roth; Paul H. Siegel

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arXiv · 1912.12748

On Bi-Modal Constrained Coding

Ron M. Roth·Paul H. Siegel

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Abstract

Bi-modal (respectively, multi-modal) constrained coding refers to an encoding model whereby a user input block can be mapped to two (respectively, multiple) codewords. In current storage applications, such as optical disks, multi-modal coding allows to achieve DC control, in addition to satisfying the runlength limited (RLL) constraint specified by the recording channel. In this work, a study is initiated on bi-modal fixed-length constrained encoders. Necessary and sufficient conditions are presented for the existence of such encoders for a given constraint. It is also shown that under somewhat stronger conditions, one can guarantee a bi-modal encoder with finite decoding delay.

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Ron M. Roth, Paul H. Siegel. 2019-12-29. On Bi-Modal Constrained Coding. https://arxiv.org/abs/1912.12748

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