Statistically Bounding Detection Latency in Low-Duty-Cycled Sensor Networks

Yanmin Zhu

doi:10.1155/2012/365421

Abstract

Detecting abnormal events represents an important family of applications for wireless sensor networks. To achieve high performance of event detection, a sensor network should stay active most of the time, which is energy inefficient for battery driven sensor networks. This paper studies the fundamental problem of bounding detection delays when the sensor network is low duty cycled. We propose a novel approach for statistically bounding detection latency for event detection in sensor networks. The key issue is the wakeup scheduling of sensor nodes and minimization of wakeup activity. We propose a lightweight distributed algorithm for coordinating the wakeup scheduling of the sensor nodes. A distinctive feature of this algorithm is that it ensures that the detection delay of any event occurring anywhere in the sensing field is statistically bounded. In addition, the algorithm exposes a convenient interface for users to define the requirement on detection latency, thereby tuning the intrinsic tradeoff between energy efficiency and event detection performance. Extensive simulations have been conducted and results demonstrate that this algorithm can successfully meet delay bound and significantly reduce energy consumption.

Highlights

Recent years have witnessed the rapid development of wireless sensor networks
Energy efficiency is critical since the battery-powered system is supposed to be continuously functional for months or even years
We have investigated the probabilistic approach to distributed event detection in sensor networks

Summary

Introduction

Recent years have witnessed the rapid development of wireless sensor networks. The surge of interest in sensor networks is driven by the promising advantage of sensor network as a low-cost solution to a wide range of realworld challenges [1,2,3,4,5,6]. Only a fraction of sensors are selected to be active, and the rest are put into sleep mode The advantage of these algorithms is that no detection latency is incurred. Recent study [6, 14] has shown that to guarantee full sensing coverage of the field, the density of sensors needs to be high This implies that an event can possibly be detected by several ambient sensors. The overdetection problem strongly motivates the idea that the duty cycle of each sensor should be reduced for better energy efficiency. We propose an innovative wakeup scheduling algorithm called PAD for energy-efficient event detection. (i) By recognizing the essential latency-tolerant property of event detection applications, we investigate the energy-efficient approach for event detection, which addresses the serious overdetection problem.

System Model and Problem Description

Analysis of DoC and Detection Delay

Probabilistic Wakeup

Evaluation

Related Work

Conclusion