Towards reliable scheduling schemes for long-lived replaceable sensor networks

To address energy constraint problem in sensor networks, node reclamation and replacement strategy has been proposed for networks accessible to human beings and robots. The major challenge in realizing the strategy is how to minimize the system maintenance cost, especially the frequency in replacing sensor nodes with limited number of backup nodes. New duty cycle scheduling schemes are required in order to address the challenge. Tong et al. have proposed a staircase-based scheme address the problem based on ideal assumptions of sensor nodes that are free of failure and have regular energy consumption rate. Since sensor nodes are often deployed in outdoor unattended environment, node failures are inevitable. Energy consumption rates of sensor nodes are irregular due to manufacture or environmental reasons. Hence, this paper proposes several new schemes to achieve reliable scheduling for node reclamation and replacement. Extensive simulations have been conducted to verify that the proposed scheme is effective and efficient.