# Annals of Computer Science and Information Systems, Volume 11

## Distance-2 Collision-Free Broadcast Scheduling in Wireless Networks

### Valentin Pollet, Vincent Boudet, Jean-Claude König

Citation: Proceedings of the 2017 Federated Conference on Computer Science and Information Systems, M. Ganzha, L. Maciaszek, M. Paprzycki (eds). ACSIS, Vol. 11, pages 469472 ()

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Abstract. In this paper, we study the distance-2 broadcast scheduling problem in synchronous wireless networks of known topology. Two constraints are taken under consideration: the schedule must be collision-free and the nodes at distance $2$ must be informed by nodes at distance $1$. In general graphs, a tight bound of $\mathcal{O}(\log(n)^2)$ slots to complete the broadcast is known, $n$ being the number of nodes at distance 2. We improve this bound to $\mathcal{O}(\log(n))$ in unit disk graphs, and to $\mathcal{O}(1)$ when the neighbourhoods of the nodes are circular intervals.

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