Maximizing Broadcast Tree Lifetime in Wireless Ad Hoc Networks

In wireless ad hoc networks (WANETs), e.g. wireless sensor networks, battery-powered devices are constrained by limited amount of energy. Many WANET applications require that the duration (called lifetime) for which the network remains operational until the first node exhausts its battery energy is maximized. We study the problem of maximizing the lifetime of WANET broadcast trees under two receiver cost models: 1) the constant receiver power (CORP) model, in which a receiver consumes a fixed amount of energy for receiving an information bit; and, 2) the transmitter-receiver power tradeoff (TREPT) model, in which the amount of energy consumed by a receiver is a function of the received signal power and hence the transmitter power. We propose a graph theoretic solution for CORP model to find a maximum lifetime tree and a binary search based solution for TREPT model to determine power assignment which maximizes the lifetime of a given broadcast tree. Both polynomialtime solutions are formally proved to be optimal.