Tighter bounds for the minimum energy broadcasting problem

In this paper we present a new upper bound on the approximation ratio of the minimum spanning tree heuristic for the basic problem on ad-hoc networks given by the minimum-energy broadcast routing (MEBR) problem. We introduce a new analysis allowing to establish a 6.33-approximation ratio in the 2-dimensional case, thus decreasing the previously known 7.6 upper bound (M. Flammini et al., 2004).