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arXiv · 2012.10081

A Comparison of Distance Bounds for Quasi-Twisted Codes

Martianus Frederic Ezerman·John Mark Lampos·San Ling·Buket Ozkaya·Jareena Tharnnukhroh
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Abstract

Spectral bounds on the minimum distance of quasi-twisted codes over finite fields are proposed, based on eigenvalues of polynomial matrices and the corresponding eigenspaces. They generalize the Semenov-Trifonov and Zeh-Ling bounds in a way similar to how the Roos and shift bounds extend the BCH and HT bounds for cyclic codes. The eigencodes of a quasi-twisted code in the spectral theory and the outer codes in its concatenated structure are related. A comparison based on this relation verifies that the Jensen bound always outperforms the spectral bound under special conditions, which yields a similar relation between the Lally and the spectral bounds. The performances of the Lally, Jensen and spectral bounds are presented in comparison with each other.

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Martianus Frederic Ezerman, John Mark Lampos, San Ling, Buket Ozkaya, Jareena Tharnnukhroh. 2020-12-18. A Comparison of Distance Bounds for Quasi-Twisted Codes. https://arxiv.org/abs/2012.10081

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