Maximizing Lifetime in an Energy Constrained Wireless Sensor Array using Team Optimization of Cooperating Systems

Abstract For omnidirectional wireless broadcast, if a node has sufficient power to broadcast to another node, it also has the ability to broadcast to all closer nodes. This is the wireless advantage. For the broadcast problem, one node (the source) is required to communicate to all other nodes, by a single transmission to the farthest node or using intermediate hop nodes. For a given node constellation, there exist many wireless connection trees to do this. For a known node constellation, the maximum lifetime of a single tree is equal to the minimum battery life of all the nodes. The battery life is determined by the power, if any, expended by each node. Reaching nodes far removed takes more power. The broadcast lifetime can be significantly increased by using a plurality of trees switching from tree to tree in accordance to a prescribed duty cycle. Using the viability lemma, we propose an evolutionary team optimization of cooperating systems to determine the best team of broadcast trees along with specified duty cycles to maximize the lifetime of a given node constellation with specified battery reserves.