Maximizing the Number of Broadcast Operations in Random Geometric Ad Hoc Wireless Networks

Tiziana Calamoneri, Andrea E.F. Clementi, Emanuele G. Fusco, Riccardo Silvestri
2011 IEEE Transactions on Parallel and Distributed Systems  
We consider static ad-hoc wireless networks whose nodes, equipped with the same initial battery charge, may dynamically change their transmission range. When a node v transmits with range r(v), its battery charge is decreased by β r(v) 2 where β > 0 is a fixed constant. The goal is to provide a range assignment schedule that maximizes the number of broadcast operations from a given source (this number is denoted as the length of the schedule). This maximization problem, denoted as Max LifeTime,
more » ... is known to be NP-hard and the best algorithm yields worst-case approximation ratio Θ(log n), where n is the number of nodes of the network. We consider random geometric instances formed by selecting n points independently and uniformly at random from a square of side length √ n in the Euclidean plane. We present an efficient algorithm that constructs a range assignment schedule having length not smaller than 1/12 of the optimum with high probability. Then we design an efficient distributed version of the above algorithm where nodes initially know * An extended abstract of this work has been presented at OPODIS 2007. n and their own position only. The resulting schedule guarantees the same approximation ratio achieved by the centralized version thus obtaining the first distributed algorithm having provably-good performance for this problem.
doi:10.1109/tpds.2010.77 fatcat:c3twbk55bnbapgrragwpdr7uaa