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On the Selection of Guided Scrambling Sequences that Provide Guaranteed Maximum Run-length Constraints

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Abstract

Guided scrambling is a coding technique that generates for each possible source word a fixed set of candidate code words and subsequently selects the "best" word subject to given channel constraints. The resulting codes are often referred to as "weak" constraint codes because they do not strictly guarantee that the specified constraints will be fulfilled. In this paper , it will be shown that for the important class of maximum run-length constraints a proper selection of the set of guided scrambling sequences can actually guarantee that the code satisfies "strong" constraints. Sequence set selections and code constructions that result in "strong" maximum run-length constraints wilt be presented.
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