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arXiv · 1107.5523

An Algebraic Approach for Decoding Spread Codes

Elisa Gorla·Felice Manganiello·Joachim Rosenthal
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Abstract

In this paper we study spread codes: a family of constant-dimension codes for random linear network coding. In other words, the codewords are full-rank matrices of size (k x n) with entries in a finite field F_q. Spread codes are a family of optimal codes with maximal minimum distance. We give a minimum-distance decoding algorithm which requires O((n-k)k^3) operations over an extension field F_{q^k}. Our algorithm is more efficient than the previous ones in the literature, when the dimension k of the codewords is small with respect to n. The decoding algorithm takes advantage of the algebraic structure of the code, and it uses original results on minors of a matrix and on the factorization of polynomials over finite fields.

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Elisa Gorla, Felice Manganiello, Joachim Rosenthal. 2012-06-06. An Algebraic Approach for Decoding Spread Codes. https://arxiv.org/abs/1107.5523

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