Modeling And Performance Analysis Of Wireless Sensor Network Systems Using Petri Nets

Wireless sensor network (WSN), composed by sensors, microprocessor and wireless communication interface, is an interesting field, and gains more and more attentions. The importance of sensor networks is highlighted by the number of recent funding initiatives, including the DARPA SENSIT program, military programs, and NSF Programs. As a brand new technology of acquiring and disposal of information, it developed rapidly in some fields such as health care, environment monitoring and military field. And localization, which has been focused as a basic problem, is the precondition of all these applications. So the research of theories of nodes' localization has both great significances for theoretic and application.The communication between nodes is the base of nodes localization on all systems. With the increasing demand of the network services, the complexity of network systems is represented through space distribution, concurrence, asynchronism, instability and diversity. Systems engineering methods are required to design and maintain the systems during the lifecycle of systems. And the mathematic graphics are also needed to formalize systems, in order to check validity, evaluate performance, realize the design goals and test systems. It will be facility for the system users to understanding itself. Due to the increasing complexity of practical problems, the demand for the formal technologies to solve these problems is growing.In this thesis, we discuss the self-localization technology in detail. Since the nodes are restricted by size, cost, energy, and work under the environment that should not be accessed, the basic approach is to use beacons that aware of their positions as reference, and the other nodes compute their positions through the relationship of distance, angel, or network connectivity to the beacons.Petri net is an outstanding graphical formal model, with its intuition and being easy to understand and use. It's fit to describe the behavioral properties of concurrent and distributing systems. We can obtain the information of system behaviors using the verification techniques of Petri net on object systems. This thesis laid a strong emphasis on modeling of wireless sensor networks. At the end, we apply the model to the localization of the nodes of a simple sensor network and gained great localization efficiency.