Breach-Free Sleep-Wakeup Scheduling for Barrier Coverage With Heterogeneous Wireless Sensors

Barrier Coverage plays a vital role in wireless sensor networks. Research on barrier coverage has mainly focused on the lifetime maximization and the critical conditions to achieve $k$ -Barrier Coverage under various sensing models. When sensors are randomly deployed along the boundary of an area of interest, they may form several disjoint barrier covers. To maximize the lifetime of barrier coverage, those barrier covers need to be scheduled to avoid a security problem, call breach. In a heterogeneous wireless sensor network, given a set of barrier-covers each with a lifetime, we study the problem of finding a lifetime-maximizing subset with a breach-free sleep-wakeup scheduling. We first prove that it can be judged in polynomial time whether a given sleep-wakeup schedule is breach-free or not, but given a set of barrier-covers, it is NP-Complete to determine whether there exists a breach-free schedule. Then, we show that the problem of finding a lifetime-maximizing breach-free schedule is equivalent to the maximum node weighted path problem in a directed graph, and design a parameterized algorithm. Experimental results show that our algorithm significantly outperforms the heuristics proposed in the literature.