Reliable Transmission Protocol Of Correlated Data In Wireless Sensor Networks

Due to overlapped coverage caused by densely deployed sensor nodes, redundant information contained in correlated data and reported separately by different sensor nodes wastes limited recourses and communication bandwidth. This thesis focuses on the research of data correlation and reliable transmission.The work of this thesis is a part of the National Natural Science Foundation Project "On the research of effective protection mechanism of data aggregation in Wireless Sensor Networks". The thesis first prospects the characteristics and applications of Wireless Sensor Networks (WSNs), and discuses the process of information gathering with an example. Because WSNs are constrained by resources, many researches are trying to economize the limited resources. In the related work, we first analyze the method of in-network processing—data aggregation, which could successfully decrease the redundant information. However, it could not solve all the problems mentioned, so we then study the methods of reliable transmission, including multi-coverage, multi-path and data retransmission.ChapterⅣfocuses on the principle of reliable transmission protocol of correlation data. Beginning with a scenario of emergency reporting, it explores the network model and information model, and presents the concept of information value to measure the usefulness of data packets. It also provides the method to compute the neighbor contribution of information value according to data correlation. At last, it discusses the way of reliable transmission using existing routing protocols. Chapter V describes the implementation of the reliable transmission protocol of correlation data, including the processes of routing establishment and maintenance, data reporting, data monitoring, data forwarding, etc.The simulation results show that, compared with the method without doing data correlation processing, the method doing data correlation processing could guarantee the information transmitted to the sink node reliably. By subtracting redundancy from packets, it suppresses data transmission and its latency, economizes energy, and thus prolongs the lifetime of sensor networks. Dominant in good performances, the protocol presented in this thesis can be applied to WSNs, especially the emergency reporting system.