Delay and lifetime issues for wireless sensor networks

Abstract

The network delay and power consumptions are the two main factors governing the efficiency of wireless sensor networks. In this paper, our goal is to minimize the delay and maximize the lifespan of event-based wireless sensor networks in which activities occur infrequently. In such architectures, most of the power is fed on when the radios are on, ready for a packet to arrive. Sleep–wake scheduling is a highly efficient mechanism to prolong the lifetime of these power-constrained wireless sensor networks. However, sleep–wake scheduling could provide result with considerable delays. This research attempts to limit these delays by developing “anycast” based packet forwarding schemes that places each node opportunistically forwards a packet to the first neighboring node which wakes up amongst more than one candidate nodes. In this paper, we propose to optimize the anycast forwarding schemes by minimizing the anticipated packet-delivery delays from the sensor nodes to the sink node. Based on this analysis, we then provide a solution to the joint control problem of how to optimally manage the architecture parameters of the sleep–wake scheduling protocol and the any-cast packet-forwarding protocol to maximize the network lifetime, with reference to a constraint on the expected end-to-end packet-arriving delay.