Optimizing router locations for minimum-energy wireless networks

Energy conservation is a key issue in ad hoc wireless network operation. Placing relay nodes (routers) at appropriate locations can substantially lower the power requirements of communicating nodes, thereby reducing overall energy needs. We investigate router placement (RP) for energy-constrained wireless networks, and present RP algorithms that aim to minimize total energy consumption. We consider the RP problem for multi-hop wireless networks, and develop an efficient heuristic solution for them. We model multiple-router placement as a clustering optimization problem in which routers and nodes are treated as clusterheads and cluster members, respectively. We also devise a heuristic that discovers the central area of a multi-hop network, and solves the RP problem with multi-hop connectivity. Simulation results confirm that our RP methods reduce the energy consumption of wireless networks by up to 55% compared with grid networks.