Research On Lifetime-Prolonging Topology Control Algorithms For Heterogeneous Wireless Sensor Networks

Due to the heterogeneous wireless sensor networks has the characteristics of energy limited and unbalanced energy consumption,node failures are usually happened,node failures and run out of energy have serious impact on network performance.Therefore,prolong network lifetime is one of the main problems in heterogeneous wireless sensor networks.Topology control is an important technology to reduce nodes energy consumption,which by adjusting the transmission range of each node or intermittently making nodes dormancy to construct a topology structure with some global properties(such connectivity and fault tolerance).Topology control technology provides a new method to node failures and unbalanced energy consumption research in heterogeneous wireless sensor networks.Aiming at the characteristics that the power consumption of heterogeneous wireless sensor network backbone is too large,this thesis constructs a kind of backbone topology structure based on connecting dominates sets to balance energy consumption,adopts sleep scheduling strategy to save nodes energy consumption.And the method how to prolong network lifetime is studied in this paper.The main work is as follows:(1)First,this thesis analyses characteristics of the heterogeneous wireless sensor networks.The challenge in wireless sensor networks and the importance of topology technology are explained.Then through analysis of the existing topology control algorithms based on connected dominating sets,the author finds that these algorithms have a short network lifetime,further finds that this is due to the unbalanced energy consumption.(2)Aming at the combined optimization problem that improving fault tolerance of backbone network,prolonging the network life cycle and maintaining the size of a small backbone,a network lifetime model and a kind of distributed lifetime-extended fault-tolerant connected dominating sets topology control algorithm(TkCDS)are proposed.TkCDS algorithm using the ideas of coloring algorithm,considering the lifetime of the nodes and node degree,constructs a lifetime-extended and fault-tolerant backbone network.Theoretical analyses prove that the size of CDS construted by TkCDS algorithm has a bounded size and CDS is k-connceted.The experimental results show that TkCDS algorithm can effectively prolong network lifetime and keep a small CDS size.(3)Aiming at the unbalanced energy consumption problem already exists after adopting the above method,this thesis proposes a lifetime-extended connected dominating set construction algorithm(TCDS)which combines power control strategy with sleep scheduling strategy.TCDS algorithm adopts the minimum connected dominating set theory to construct a backbone topology,and combining with the ideas of power control to reduce nodes energy consumption.Theoretical analyses prove that the network constructed by TCDS algorithm is connected and the CDS size is bounded.The experimental results show that TkCDS algorithm can prolong network lifetime by nearly 15.3%compared with CDS-BD-D algorithm.The thesis designs a simulation platform of topology control algorithm based on the Eclipse tool.Since the platform joins the energy consumption model,propagation model and data fusion model,it is close to the real network.