Nested Block Decodable Runlength Limited Codes

Hogan, Josh ; Roth, Ron M. ; Ruckenstein, Gitit

HP Development Company

关键词: block decodable encoders;    deterministic encoders;    nested encoders;    runlength-limited constraints;   

RP-ID  :  HPL-2000-91

学科分类：计算机科学（综合）

美国|英语

来源: HP Labs

【 摘 要 】

Consider a (d(subscript 1), k(subscript 1))-RLL constraint that is contained in a (d(subscript 2), k(subscript 2)-RLL constraint, where k(subscript 1) >2d(subscript 1) and d(subscript 2) > 0, and fix a codeword length q> k(subscript 2). It is shown that whenever there exist block decodable encoders with codeword length q for those two constraints, there exist such encoders where one is a subgraph of the other; furthermore, both encoders can be decoded by essentially the same decoder. Specifically , a (d(subscript 1),k(subscript 1)-RLL constrained word is decoded by first using a block decoder of the (d(subscript 2,k(subscript 2)-RLL encoder, and then applying a certain function to the output of that decoder. Notes: This abstract contains formulae which cannot be accurately reproduced here. 25 Pages