Improved upper bound for the redundancy of fix-free codes

@article{Yekhanin2004ImprovedUB,
  title={Improved upper bound for the redundancy of fix-free codes},
  author={Sergey Yekhanin},
  journal={IEEE Transactions on Information Theory},
  year={2004},
  volume={50},
  pages={2815-2818}
}
  • S. Yekhanin
  • Published 15 September 2003
  • Mathematics, Computer Science
  • IEEE Transactions on Information Theory
A variable-length code is a fix-free code if no codeword is a prefix or a suffix of any other codeword. In a fix-free code, any finite sequence of codewords can be decoded in both directions, which can improve the robustness to channel noise and speed up the decoding process. In this paper, we prove a new sufficient condition of the existence of fix-free codes and improve the upper bound on the redundancy of optimal fix-free codes. 
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Some Tight Lower Bounds on the Redundancy of Optimal Binary Prefix-Free and Fix-Free Codes
TLDR
It is proven that the tight lower bound in terms of the probability of the most likely symbol is the same for optimal prefix-free and optimal fix-free codes.
On the 3/4-Conjecture for Fix-Free Codes -- A Survey
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Since any code has Kraftsum smaller than or equal to one, this answers the question for the second implication of Kraft-McMillan's theorem.
On the capability of the Harada-Kobayashi algorithm in finding fix-free codewords
The capability of the Harada-Kobayashi algorithm in finding fix-free codewords is examined. For n les 30, it is observed that this algorithm finds fix-free codewords for more than 99 percent of
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