The Target-Barrier Coverage Problem in Wireless Sensor Networks

In this paper, we define a new type of coverage problem named target-barrier coverage problem in wireless sensor networks. A target-barrier is a continuous circular barrier formed around the target. The target-barrier has a <inline-formula><tex-math notation="LaTeX">$d_{bound}$</tex-math><alternatives> <inline-graphic xlink:href="cheng-ieq1-2751040.gif"/></alternatives></inline-formula> constraint that is set depending on applications and needs, where <inline-formula><tex-math notation="LaTeX">$d_{bound}$</tex-math><alternatives> <inline-graphic xlink:href="cheng-ieq2-2751040.gif"/></alternatives></inline-formula> is the minimum distance of the constructed barrier from the target. Target-barrier coverage is very suited for application in defense surveillance, including detection of intrusion from outside and prevention of barrier breaching from inside. For instance, in a jail scenario, sensors can be deployed to enclose a jail with the constraint of <inline-formula><tex-math notation="LaTeX"> $d_{bound}$</tex-math><alternatives><inline-graphic xlink:href="cheng-ieq3-2751040.gif"/></alternatives> </inline-formula> to detect the escape of prisoners or unauthorized entry into the jail for rescuing prisoners. We focus on how to minimize the number of members required to construct target-barriers in a distributed manner while satisfying the <inline-formula><tex-math notation="LaTeX">$d_{bound}$</tex-math><alternatives> <inline-graphic xlink:href="cheng-ieq4-2751040.gif"/></alternatives></inline-formula> constraint and minimizing the amount of message exchange required. In performance evaluation, we compare our solution with the solution of related work and the Brute-Force algorithm which can find the minimum number of target-barrier members required. Our experimental results show that the proposed algorithm delivers satisfactory results in terms of the number of target-barrier members required and the amount of message exchange required.