Research On Data Gathering In Wireless Sensor Network

With the rapid development of micro electro mechanical systems, system on a chip,wireless communication technology and low-power embedded technology, and thetrend to cheapness of wireless sensor nodes, wireless sensor network has been appliedin varieties of occasions. Moreover, because of its features such as low power, low cost,distribution and self-organization, WSN draws more and more attention and study.However, sensor nodes have some inherent defects, for example, the weak ability ofcomputing, communication distance is limited and reliability is low. As a result, how togather information from the distributed nodes, namely data gathering, has become animportant and challenging work. To some extent, it determines the network lifetime.Against the data gathering in WSN, the paper takes the aim to prolong the networklifetime and reduce the latency, and study the data gathering algorithms in differentpractical occasions. At last, we provide two solutions to the problem, and verify theirperformance through simulation. The following is the concrete detail.①In order to prolong the network lifetime and reduce the data gathering latency,we provide a data gathering algorithm with two-tier structure. In the Sensor layer, bymeans of the research to the residual energy, an energy efficient cluster algorithm ofadaptive division is put forward. Because the clustering algorithm is based on theresidual energy of the nodes, the cluster head should be those nodes with higher residualenergy so that the network resources are allocated reasonably. At the same time, eachcluster is assigned two cluster head, which reduces the energy burden of cluster head.As a result, the network lifetime is prolonged. In the Sencar layer, firstly, we load theSencar with dual antenna that nodes can upload data by MIMO to reduce the total datagathering latency. Then through the TSP method, the Sencar can choose an optimalmigration path. So we can reduce data gathering latency from the aspect of migrationlength. In addition, we propose a kind of optimal speed control plan, the speed of theSencar can keep in the best condition all the time. So the total data gathering latency isimproved from the aspect of mobile speed. Compared with the existing algorithms, theexperiment indicates that this method can balance the network traffic, prolong thenetwork lifetime and data gathering latency is short.②Considering the wireless sensor network situation deployed rechargeable sensornodes, we adopt the mobile data gathering model. Firstly, we propose a joint anchor selection algorithm and combine the charging process with data gathering process tosimplify the WSN model. Meanwhile Sencar can communicate with Sink constantly,which brings about the combination of the static data gathering model and the mobiledata gathering model. Then, based on the priority about time, position and TSP problemrespectively, we give three mobile strategies of the Sencar. At last, we use utilityfunction to measure the amount of collected data, which make the node generate andtransmit data at the best efficiency. Through the simulation experiment, this method canimprove the data transmission rate, and can reduce the moving path of Sencar.