Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
449593 | Computer Communications | 2007 | 11 Pages |
In this paper, we discuss the energy efficient multicast problem in ad hoc wireless networks. Each node in the network is assumed to have a fixed level of transmission power. The problem of our concern is: given an ad hoc wireless network and a multicast request, how to find a multicast tree such that the total energy cost of the multicast tree is minimized. We first prove this problem is NP-hard and it is unlikely to have an approximation algorithm with a constant performance ratio of the number of nodes in the network. We then propose an algorithm based on the directed Steiner tree method that has a theoretically guaranteed approximation performance ratio. We also propose two efficient heuristics, node-join-tree (NJT) and tree-join-tree (TJT) algorithms. The NJT algorithm can be easily implemented in a distributed fashion. Extensive simulations have been conducted to compare with other methods and the results have shown significant improvement on energy efficiency of the proposed algorithms.