Study On Topology Control Algorithm Of Wireless Sensor Network Based On Shortest Path Tree

As a new type of measuring and controlling networks, wireless sensor networks have hugely potential application value in military, industry, environmental, medical and many other fields, due to which has caused widespread attention of domestic and abroad researchers. Given their limited energy, to maximize the reduction of energy consumption and maintain network performance has been the main design target of networks. Topology control is a key technology which effectively enhances the energy efficiency of wireless sensor networks and it is of great significance for prolonging network lifetime, improving network performance and so on. Therefore, studying on efficient network topology control algorithms has theoretical and practical significance. Start with topology models, the topology algorithms based on shortest path tree have been studied in this dissertation.Typical topology models of proximity graph for wireless sensor networks, such as UDG, MST, RNG, GG and so on have been analyzed. Considering the limitations that these models constructed topologies can not evaluate the actual characteristics of networks, the law of energy consumption on patterns of one hop and multi hop communication has been studied in the light of energy consumption of nodes communication. Combining with the idea of shortest path increasing by degrees of Dijkstra algorithm, an algorithm constructing the minimal energy-consuming path topology has been proposed. Accordingly a topology model based on shortest path tree has been established, which can obtain the minimal energy-consuming path from every node to the destination node.By the analysis on data transmission paths, a topology algorithm based on the local minimal energy-consuming path tree (LMPT) has been designed, which initiates the topology discovery process with the sink node, then uses a timer in direct proportion to the communication energy consumption between nodes to control the order of nodes joining topology, and the minimal energy-consuming path tree has been built by energy consumption increasing of paths. Meanwhile the topology maintenance method has also been researched to solve the problem of some prematurely invalid nodes because of heavy load. The theory and simulation analysis shows the efficiency of LMPT algorithm.The relationship between network performance and topology structure has been discussed for wireless sensor networks. Aiming at problems of communication conflict among nodes and network performance degradation resulted from excessive neighbor nodes, a Degree-optimized local minimal energy-consuming path tree topology control algorithm (DLPT) has been presented, which uses the relative neighborhood graph method to optimize the number of neighbor nodes. The theoretical analysis proves the connectivity and degree bound of topology derived under this algorithm. The experiment results show that the topology has advantages on node degree and transmission power efficiency, as well as smaller path energy consumption, which can improve the whole network performance and prolong the network lifetime.