In order to improve the reliability and availability of industrial wireless sensor network (WSN), and to make WSN autonomously work for a long lifetime, a cluster- based routing algorithm for industrial WSN based on the redundancy of cluster-heads was given. When the master cluster-head has not enough energy or has a failure, the redundant cluster-head can take over the data transmission tasks. The marginal nodes use the backup cluster-head and a multi-cluster access scheme to tolerate the failure of cluster- heads. For the isolated nodes that cannot communicate with any cluster-head directly, a multi-hop routing technique based on the probability model was put forward to maintain the normal communication. In addition, the presented algorithm sets the redundant cluster-head into the light-weighted sleeping state, and closes the front end radio frequency components when the redundant testing cycle comes so as to reduce the energy consumption. With the presented sensor nodes, an experimental environment was setup and three experiments were implemented, including cluster-head switching, marginal nodes and isolated nodes communication mechanisms. Experimental results showed that the proposed cluster-based routing algorithm has higher reliability than that of the single cluster-head network model．
FENG Dong-Qin, LI Guang-Hui, QUAN Jian-Min, et al. Reliability of wireless sensor networks based on redundancy of cluster-heads. J4, 2009, 43(5): 849-854.
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