On the Design of k-Covered Wireless Sensor Networks: Self-versus Triggered Sensor Scheduling

Sensing coverage reflects the quality of surveillance of a field by a wireless sensor network (WSN). This paper investigates the problem of minimum connected k-coverage in WSNs, where each point in a field is covered (or sensed) by at least k active sensors while minimizing the necessary total number of active sensors and ensuring connectivity, between them. In this paper, we propose two k-coverage protocols using different scheduling approaches. In the first protocol, called Self-Scheduling driven k-Coverage (SSCk), each sensor turns itself on based on the local information has about its sensing neighbors in order to k-cover its sensing range. The second protocol, called Triggered-Scheduling driven k-Coverage (TSCk), allows a sensor to trigger a necessary number of its sensing neighbors to become active in order to achieve k-coverage of its sensing range. Then, we relax some commonly used assumptions for coverage configuration protocols in WSNs to promote the use of SSCk and TSCk. in real-world sensing applications. Simulation results show that TSCk. outperforms SSCk. with regard to the number of sensors required for connected k-coverage as well as the network lifetime. We find that SSCk outperforms an existing connected k-coverage protocol for WSNs.