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arXiv · 1811.03789

Construction of isodual codes from polycirculant matrices

Minjia Shi·Li Xu·Patrick Sole
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Abstract

Double polycirculant codes are introduced here as a generalization of double circulant codes. When the matrix of the polyshift is a companion matrix of a trinomial, we show that such a code is isodual, hence formally self-dual. Numerical examples show that the codes constructed have optimal or quasi-optimal parameters amongst formally self-dual codes. Self-duality, the trivial case of isoduality, can only occur over $ \F_2$ in the double circulant case. Building on an explicit infinite sequence of irreducible trinomials over $\F_2,$ we show that binary double polycirculant codes are asymptotically good.

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Minjia Shi, Li Xu, Patrick Sole. 2018-11-09. Construction of isodual codes from polycirculant matrices. https://arxiv.org/abs/1811.03789

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