Research On Key Techniques Of Data Reliable Transmission In Wireless Sensor Network

With the continuous development of wireless sensor network, its applications become more and more widely. However, data transmission of WSN requires high reliability in many applications. In some particularly harsh environments, wireless sensor network is often affected by complex environment, attenuation, multi-path, dead-zone, node performance and other factors, which will easily lead to errors and data packet loss in data transmission process, data reliable transmission can not be guaranteed. Therefore, reliable data transmission has become a significant problem in the research of wireless sensor network.On the basis of analyzing and summarizing data reliable transmission research status, related research fields and research methods for WSN, focusing on the lack of reliable data transmission research in wireless sensor network, the research goal and outline are proposed, and related research results are as follows:First, study on data reliable transmission based on energy balance in WSN. In view of energy load uneven distribution of WSN, some nodes will die prematurely due to excessive energy consumption, which lead to interruption of communication links and data packet loss, thus reliable data transmission is affected. On the basis of analyzing the main factors that affect energy consumption and existing energy saving technologies, combined with application of virtual multiple-input multiple-output (Virtual MIMO) routing algorithm in isomorphic wireless sensor network, virtual multiple-input multiple-output clustering algorithm (VMMCA) which applies to small and medium scale isomorphic WSN is proposed. VMMCA not only can select cluster head randomly, but also can achieve the life cycle optimization of WSN on the premise of assuring nodes communication quality. Virtual MIMO cluster network energy consumption model is established. On the condition of changing for different clusters size, node distribution density, the path loss index and sink nodes, the change of the energy consumption of virtual MIMO network and SISO network is analyzed. In order to balance network energy load and prolong lifetime of WSN, and the network lifetime is taken as the optimization target, the ratio of the clusters head is optimized by genetic algorithm. The experiment and simulation results show that compared with LEACH algorithm, VMMCA can achieve very good balance of energy and prolong network lifetime.Second, links metric based on multi-dimensional Gaussian autoregressive model in WSN. In order to meet the demand of detection events information reliability and maximize network life cycle, the cooperative routing strategy based on multi-dimensional Gaussian autoregressive model is proposed. The cooperative routing strategy adopts multi-dimensional Gaussian autoregressive model to analyze information correlation within the detection field, and the participation of each link on a path is quantized to reduce the error probability when making final decision at the fusion center. Only new information instead of whole original data is included when sensed information is propagated to fusion center by sensor nodes, and using the quick filter to aggregate data information at intermediate nodes along the path to the fusion center. In order to balance detection reliability and energy efficience, and energy consumption weighted value is introduced in the expression of the detection reliability-aware link metric. Simulation results show that at a given detection reliability standards, compared with non-cooperative routing strategies and traditional minimum energy routing policy, the proposed cooperative routing strategy has been significantly improved in terms of energy efficiency and reliability of detection.Third, study on data reliable transmission based on link quality indication in wireless sensor network. The influence of antenna orientation, communication distance, transmission power, supply voltage and external dynamic environment on LQI mean and Coefficient Variance (CV) is verified by experiment, and on the basis of it, a kind of routing metric model based on LQI mean and CV (RMBLQICV) is constructed. In order to effectively evaluate the merits of data transmission, choose the best transmission path, and RMBLQICV model dynamically combines LQI mean and CV to evaluate the quality of paths, thus it effectively reduces the appearing likelihood of bottleneck link and improves reliability of data transmission. Aiming at lack of a classic on-demand routing protocol, the on-demand routing protocol AODV is improved, and combine proposed RMBLQICV to obtain Multipath Routing Protocol (LBM_AODV) based on mean LQI. RMBLQICV model and LBM_AODV protocol are verified through the experimental platform which takes CC2430as transceivers, the experiment results show that compared with LQI mean model, RMBLQICV routing metric model effectively avoid misjudgment in terms of choice of the path, and accurately eliminate the paths which contain bottleneck link, data reliable transmission is greatly improved.Fourth, study on data reliable transmission based on link aware in three-dimensional wireless sensor network. In order to describe behavior of air wireless sensor network communication links, the performance and reliable data transmission of links in the outdoor environment are studied. A series of experiments based on CC2430wireless sensor platform are designed to observe various factors that affect performance of AWSN in detail. The experiment results show that, in addition to usual outdoor environmental factors affecting the link performance, two important factors to the link degradation in aerial wireless sensor networks are direction of antenna and multipath fading due to reflections of the ground. On the basis of fully considering factors affecting performance degradation of link, a kind of data reliable transmission protocol based on link aware in WSN (DRTPLA_WSN) is proposed, and the agreement design and performance assessment are analyzed in detail, DRTPLA_WSN is evaluated in tolerate delay and real-time requirements AWSN environment respectively. Simulation results show that, DRTPLA_WSN effectively improve the overall performance of network, packet loss rate decrease significantly for real-time transmission air wireless sensor networks, which greatly improves the reliability of network and saves energy consumption of network.