Research On Clustering Topology Control Algorithms For Wireless Sensor Networks

How to effectively balance energy consumption of nodes and prolong the survival time of the network is one of the research hot spots for clustering topology control algorithms of wireless sensor networks. The network is divided into multiple levels of data transmission subnet by selecting the appreciate cluster heads in clustering topology control strategy, it has unique advantages in energy efficiency and scalability, and sleep scheduling of sensor nodes can also be applied to clustering topology. Based on clustering ways of nodes, the mechanism of cluster head selection and the establishment of single or multi-hop data transmission path in the clustering topology control algorithm, this thesis mainly focuses on the analysis of the energy-saving and energy balance for wireless sensor networks. The specific contents are as follows:1. Distance in the existing clustering topology control algorithms cannot reflect the communication cost between nodes, because it does not consider the energy factor of nodes. This thesis defines Energy Distance based on the residual energy of destination nodes and the path loss between nodes as neighbor node selection criteria. First, this thesis uses static clustering, and the monitoring area is divided into several sub-regions. Second, based on the considerations of energy-efficiency and Energy Distance, nodes in the network form a multi-chain topology, and sensor nodes in each sub-region select cluster head based on the residual energy and the distance between the Base Station. A tree structure is formed by cluster heads based on Energy Distance to avoid producing long distance communication. Simulation results show that the proposed algorithm has better comprehensive performance at the survival time and the energy balance of the network, and reduces the rate of network energy consumption of the network.2. Due to that the existing clustering ways do not consider enough factors that have an effect on energy consumption of nodes, and does not consider the performance of cluster structure, a clustering topology control algorithm for wireless sensor networks based on wireless signal irregularity is proposed. First, this algorithm achieves static clustering by region partition factor which is defined on the basis of wireless signal irregularity model. Second, the phase of selecting cluster heads is divided into two phases, which are selection of candidate cluster heads and determination of final cluster heads respectively. The stability of the clustering structure is modeled based on the reliability theory model after nodes becoming cluster heads, and the threshold formula of cluster heads selection is improved combined with the stability of cluster structure. Nodes with the highest stability become the candidate cluster heads, and the determination of cluster heads is on the basis of the candidate cluster heads' location in each cluster to balance the energy consumption of nodes. A planar topology is formed among cluster heads to avoid network segmentation due to the sudden failure of a relay cluster head. Simulation results show that the proposed algorithm can prolong the survival lifetime and balance the energy consumption of nodes in the network, reduce energy consumption rate and increase the number of data packets sending to Base Station.