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Design of Close-to-Capacity Constrained Codes for Multi-Level Optical Recording

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Abstract

We report a new method for designing (M,d, k) constrained codes for use in multi-level optical recording channels. The method allow us to design practical codes, which have simple encoder tables and decoders having fixed window length. The codes presented here for the d = 1 and d = 2 cases, achieve higher storage densities than previously reported codes, and come within 0.3 - 0.7% of capacity.

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