A Study On Connectivity And Coverage In Wireless Sensor Network

With the development of information technologies, it is possible to integrate the computing, communication, networking and sensing into one tiny embedded device, Wireless sensor network is a new research area embedded of those technologies. Wireless sensor network is an important research area of Ubiquitous Computing. Integrated with sensor unit, data processor unit and communication module, tiny sensor nodes can work to form a self-organization network, to sample the environment data or monitor the environment. The research of the wireless sensor network gradually gets the focus from the industrial and academe. It has a great application future in the military and civil area.Two of the most fundamental problems in WSN are connectivity and coverage. Connectivity indicates every node can communicate with any other nodes in WSN. It is the precondition to create a self-organization network. Coverage means that overall area should be sensed by all nodes so that the observer can obtain the whole information. Connectivity and coverage not only determine the validity of a WSN, but also affect some important parameters of a WSN, for example, energy consumption, lifetime and service quality etc. So a research on connectivity and coverage has great academic and practical values.In the thesis, the basic principle and the research status worldwide of wireless sensor network are introduced briefly. And based on the relative technologies of WSN, the primary characters of WSN are abstracted. In the study on connectivity, a mathematics model is designed in the thesis. A WSN can be created by using the personal computer and developing all nodes randomly. The thesis obtains some results by the analysis of network single and multi connectivity. The results are more helpful to design a WSN in the engineering practice. A research on coverage is described in next part. The thesis classifies the problems of coverage and discusses the standards of evaluating a coverage control algorithm. Three typical algorithms: Node Self-Scheduling coverage, Worst and Best-Case coverage and Exposurecoverage are discussed principally. Their principles and techniques are studied and the virtue and defect are pointed out in the thesis. Furthermore, a method is proposed to improve the coverage of a WSN in theory. By the purposive movement of some redundant nodes, the method can improve the coverage of a network effectively.