Research On Node Dynamic Coverage Optimization And Network Segmentation In Wireless Sensor Networks

With the continuous development of sensor technology,wireless sensor network,as a new information acquisition and processing technology,has become the hotspot of current research.It is widely used in the fields of military,disaster relief,environmental monitoring,health care and space exploration.Coverage control technology is the basis of wireless sensor network applications.The coverage and connectivity directly determine the performance of the network,and also have a direct impact on the key factors such as network service quality and node lifetime.Therefore,the research on network coverage optimization and connectivity quality improvement has important theoretical significance and application value.This thesis focuses on the problem of network coverage optimization of dynamic nodes and the path selection of adaptive connectivity.The main innovation points are as follows:In the network construction process,network conditions such as network coverage,node energy consumption and connectivity cannot reach the good state at the same time due to too few constraints.Based on the traditional virtual force algorithm,a network coverage optimization algorithm based on dynamic nodes is proposed.Firstly,the information of uncovering grid is obtained by constructing the uncovering grid function.Secondly,the constraint conditions of the uncovered grid and boundary are increased,the constraints between sensor nodes are improved,and the concrete analysis methods are given to the obstacles in the network.Finally,the concept of resultant threshold is proposed,and the dynamic distribution of nodes is realized through the adaptive selection force.The simulation results show that the method can not only improve the network coverage,but also save the mobile energy consumption of sensor nodes.In practical application,due to some external factors will lead to a large area sensor nodes failure and the network connectivity has been destroyed.Aiming at this problem,this thesis proposes a new algorithm of obstacle avoidance reconnection based on network segmentation using the theory of minimum spanning tree.Firstly,the boundary sensor is defined to find the shortest link topology diagram.Secondly,this thesis give a concrete boundary node activation method to the obstacle model proposed in chapter 3,and plan the obstacle avoidance reconnection path.Finally,by considering the mobility of relay nodes,the consumption function of relay nodes is constructed,and the number and location of relays are chosen to further optimize the obstacle avoidance reconnection path and complete the reconnection of the segmentation networks.The simulation results show that this method can always choose proper relay to move,optimize the reconnection path,improve the success rate of communication and reduce the energy consumption of nodes.