Distributed Algorithms for Delay Bounded Minimum Energy Wireless Broadcasting

In this article, we investigate two different distributed algorithms for constructing a minimum power broadcast tree with a maximum depth ? which corresponds to the maximum tolerable end-to-end delay in the network. Distributed Tree Expansion (DTE) is based on an implementation of a distributed minimum spanning tree algorithm in which the tree grows at each iteration by adding a node that can cover the maximum number of currently uncovered nodes in the network with minimum incremental transmission power and without violating the delay constraint. In Distributed Link Substitution (DLS), given a feasible broadcast tree, the solution is improved by replacing expensive transmissions by transmissions at lower power levels while reserving the feasibility of the tree with respect to the delay bound. Although DTE increases the message complexity to O(n3) from O(n2?) in a network of size n, it provides up to 50% improvement in total expended power compared to DLS.