Energy -Efficient Sensor Networks for Detection Applications
S. Appadwedula · 2003
Sensor networks powered by batteries or charged by energy-scavenging devices are to be used in a wide variety of applications where detection is the primary step. Faced with tight constraints on energy, bandwidth, and other system resources, the new paradigm of decentralized detection under resource constraints has emerged. To address some of the system-level costs in a sensor network, we formulate detection problems with constraints on the cost arising from transmission (sensor nodes to a fusion center) and measure-ment (at each sensor node). For transmission, a send/no-send scheme effectively reduces how often sensor nodes must communicate while maintaining small error and false-alarm probabilities. We find that randomization over the choice of measurement and rate of transmission can meet resource constraints and maximize the detection performance. In practice, the distribution of the observations is time varying and only partially known. In-variant tests with thresholds or parameters that can be determined independently at each sensor node are necessary to avoid frequent communication between nodes. For distance metrics and for sufficiently small communication rates in Bayesian and Neyman-Pearson