Sensor selection cost function to increase network lifetime with QoS support
Yang Ou, Wendi Heinzelman · 2008
Single-hop centralized wireless sensor networks are widely used for applications ranging from security and surveillance to medical monitoring. Often the goal of these networks is to provide satisfactory quality of service (QoS) to the application under different system states, but it is difficult to determine how the appropriate sensor sets should be selected over time, given the knowledge of all possible sensor sets to support the application QoS requirements. To address this problem, in this paper we propose a novel cost function called SUI (Sensor Usage Index) that is based on a sensor's relative ideal lifetime (SRIL) and can be used to select sensor sets so as to meet application QoS requirements for extended periods of time. Simulation results show that utilizing the proposed cost function for sensor set selection enables the network to meet application QoS requirements for longer than using other standard sensor selection schemes. In fact, our scheme approaches the optimal network lifetime, which can be found using global knowledge of the sensors and the system dynamics.