Power efficient broadcasting and multicasting in wireless networks with directional antennas

Broadcasting and multicasting packets in a power efficient way is a critical task in wireless ad hoc networks. In a recent paper Li et al., (2004) study the minimum energy broadcast (MEB) routing problem in a wireless ad hoc network where every node has an omni-directional antenna and a fixed transmission power level. We extend their work to wireless networks with directional antennas in this paper. We formulate the minimum power multicasting/broadcasting using directional antennas (PMDA/PBDA) problems. For each problem, we present an approximation algorithm with worst- case approximation ratio O(log²n), where n is the number of nodes in the network. We also present several effective heuristics to solve the problems, the shortest path tree (SPT) heuristic, the directed minimum spanning tree (DMST) heuristic and a greedy heuristic. Simulation results are presented to show the performance of our algorithms.