Distributed routing for signal detection in wireless sensor networks

We study the problem of energy-efficient routing for signal detection in wireless sensor networks. Generic routing protocols use networking-centric measures such as minimum hop or minimum energy to establish routes. These schemes do not take into account the performance of application-specific algorithms that is achievable from the data collected by the nodes along the routes. Routing protocols for signal detection have recently been proposed to facilitate joint optimization of detection performance and energy efficiency by developing metrics that connect detection performance with energy consumption of each link along the routes. In existing routing for signal detection (RSD) schemes, however, the routes are computed centrally requiring complex optimization algorithms and global information such as locations and observation coefficients of all nodes in the network. Clearly, for large-scale networks, or networks with dynamically changing topologies, distributed routing schemes are more practical due to their better flexibility and scalability. We present a distributed RSD protocol where each node, based on locally available information, selects its next-hop with the goal of maximizing the detection performance associated with unit energy expenditure. We show that the proposed protocol is readily implementable in ZigBee networks, and present simulation results that reveal its significant improvements in detection performance and energy efficiency over generic routing protocols.