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arXiv · 0910.5073

A General Upper Bound on the Size of Constant-Weight Conflict-Avoiding Codes

Kenneth W. Shum·Wing Shing Wong·Chung Shue Chen
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Abstract

Conflict-avoiding codes are used in the multiple-access collision channel without feedback. The number of codewords in a conflict-avoiding code is the number of potential users that can be supported in the system. In this paper, a new upper bound on the size of conflict-avoiding codes is proved. This upper bound is general in the sense that it is applicable to all code lengths and all Hamming weights. Several existing constructions for conflict-avoiding codes, which are known to be optimal for Hamming weights equal to four and five, are shown to be optimal for all Hamming weights in general.

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Kenneth W. Shum, Wing Shing Wong, Chung Shue Chen. 2010-11-06. A General Upper Bound on the Size of Constant-Weight Conflict-Avoiding Codes. https://doi.org/10.1109/tit.2010.2048508

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