On the algebraic structure of quasi-cyclic codes of index \(1\frac {1}{2}\)


In this paper, we study quasi-cyclic codes of index \(1\frac {1}{2}\) and co-index 2m over \(\mathbb {F}_{q}\) and their dual codes, where m is a positive integer, q is a power of an odd prime and \(\gcd (m,q) = 1\). We characterize and determine the algebraic structure and the minimal generating set of quasi-cyclic codes of index \(1\frac {1}{2}\) and co-index 2m over \(\mathbb {F}_{q}\). We note that some optimal and good linear codes over \(\mathbb {F}_{q}\) can be obtained from this class of codes. Furthermore, the algebraic structure of their dual codes is given.

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The authors would like to thank the two anonymous reviewers and the Associate Editor for their valuable suggestions and comments that helped to greatly improve the paper. This research is supported by the 973 Program of China (Grant No. 2013CB834204), the National Natural Science Foundation of China (Grant No. 61571243), and the Fundamental Research Funds for the Central Universities of China.

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Correspondence to Yun Gao.

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Gao, Y., Fang, W. & Fu, F. On the algebraic structure of quasi-cyclic codes of index \(1\frac {1}{2}\). Cryptogr. Commun. 12, 1–18 (2020). https://doi.org/10.1007/s12095-019-0352-7

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  • Quasi-cyclic codes of index \(1\frac {1}{2}\)
  • Algebraic structure
  • Minimal generating set
  • Dual codes

Mathematics Subject Classification (2010)

  • 94B05
  • 94B15
  • 11T71