On Quasi-Cyclic Codes as a Generalization of Cyclic Codes

Morgan Barbier; Christophe Chabot; Guillaume Quintin

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arXiv · 1108.3754

On Quasi-Cyclic Codes as a Generalization of Cyclic Codes

Morgan Barbier·Christophe Chabot·Guillaume Quintin

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Abstract

In this article we see quasi-cyclic codes as block cyclic codes. We generalize some properties of cyclic codes to quasi-cyclic ones such as generator polynomials and ideals. Indeed we show a one-to-one correspondence between l-quasi-cyclic codes of length m and ideals of M_l(Fq)[X]/(X^m-1). This permits to construct new classes of codes, namely quasi-BCH and quasi-evaluation codes. We study the parameters of such codes and propose a decoding algorithm up to half the designed minimum distance. We even found one new quasi-cyclic code with better parameters than known [189, 11, 125]_F4 and 48 derivated codes beating the known bounds as well.

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Morgan Barbier, Christophe Chabot, Guillaume Quintin. 2011-08-18. On Quasi-Cyclic Codes as a Generalization of Cyclic Codes. https://arxiv.org/abs/1108.3754

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