The USC Andrew and Erna Viterbi School of Engineering USC Signal and Image Processing Institute USC Ming Hsieh Department of Electrical Engineering University of Southern California

Technical Report USC-SIPI-386

“Aging Analysis in Large-Scale Wireless Sensor Networks”

by Jae-Joon Lee

May 2007

Understanding the aging process of a sensor network, i.e. its performance degradation over time, is important since this information can be used for network maintenance and planning in long-term deployment. Prior research on the lifetime of wireless sensor networks has primarily focused on the energy depletion of the very first node. In this study, we analyze the aging process of the entire sensor network with respect to different network operations and deployment conditions. First, we examine the impact of node death on connectivity to the sink in a multi-hop data gathering tree. Then, we provide distance-level analysis for the dense deployment case by taking into account the re-construction of a data gathering tree and work load shift caused by energy depletion. Second, we provide an extensive study on localized topology construction schemes and their impact on the network lifetime. We present the precedence condition among these schemes in terms of network lifetime. Third, we analyze the aging process in heterogeneous deployments and derive expressions for the optimal mixture of heterogeneous devices that maximizes the lifetime coverage. We examine the spatial correlation effect on the optimal heterogeneous deployment. Our analysis explains diverse aging behaviors, which are highly dependent on the network operations and deployment conditions, and provides useful insights into long-term deployment and network maintenance and planning.

This report is not currently available in PDF format for downloading. Contact the Signal and Image Processing Institute for information on its availability.