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arXiv · 1911.03387

Combining subspace codes

Antonio Cossidente·Sascha Kurz·Giuseppe Marino·Francesco Pavese
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Abstract

In the context of constant--dimension subspace codes, an important problem is to determine the largest possible size $A_q(n, d; k)$ of codes whose codewords are $k$-subspaces of $\mathbb{F}_q^n$ with minimum subspace distance $d$. Here in order to obtain improved constructions, we investigate several approaches to combine subspace codes. This allow us to present improvements on the lower bounds for constant--dimension subspace codes for many parameters, including $A_q(10, 4; 5)$, $A_q(12, 4; 4)$, $A_q(12, 6, 6)$ and $A_q(16, 4; 4)$.

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Antonio Cossidente, Sascha Kurz, Giuseppe Marino, Francesco Pavese. 2021-11-19. Combining subspace codes. https://doi.org/10.3934/amc.2021007

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