Energy optimization for chain-based data gathering in wireless sensor networks

This paper aims to minimize energy expense for chain-based data gathering schemes, which is essential to prolong the operation lifetime of wireless sensor networks. Energy expense in chain-based data gathering schemes consists of two parts. One corresponds to inter-sensor communications and depends on chain structure. The other corresponds to leader-BS (base station) communications and depends on leader scheduling policy. To optimize inter-sensor communications, the notion of virtual chain is utilized, where an edge may correspond to a multi-hop data propagation path to conserve power. In contrast, an edge in previous work can only be a costly direct communication link. To optimize leader-BS communications, a leader scheduling rule is presented, where the node with the maximum residual power will be selected to be the leader of the chain. In contrast, nodes in previous work act as leaders by turns, resulting in non-uniform energy consumption among sensors. Simulation results show that our strategies are nearly optimal in terms of power conservation.