Research On Wireless Sensor Network Optimization Design Method For Particular QOS Requirements

With the extensive application of Wireless Sensor Network (hereafter referred to as WSN), more and more attention are being focused on the optimization design of it. Limited by self-capability of sensor nodes in WSN and the wireless transmission mode, it is hardly possible to reach the optimal level on each technical target at the same time. Thus, the concept of Quality of Service (hereafter referred to as QoS) has been brought into the design of WSN, which transform the design objective from optimization of technical target to maximization of customer satisfaction. Unfortunately, existing studies from this angle mainly concentrate on single or a minority of QoS needs and focus on a single network layer. Only few of them try to integrate multiple QoS needs in the global design of the network. This study proposes an optimized design which first dismantles multiple QoS needs of customer and then transfers them into technical targets.Firstly, based on certain QoS needs of customers, this study brings the concept of Quality Function Deployment, dismantles customer QoS needs levels, maps them into specific technical targets and acquire the importance degrees of each technical targets. Customer satisfactions are quantified and a model of optimization of technical targets is built on this basis. By determining the model of optimization of technical targets, the quantized values of different technical targets are acquired, thus to guide the global design of WSN.Secondly, after acquiring the specific technical targets, the study put an emphasis on one stage----the stage of sensor placement, and then proposes a disposition plan which meets the targets of coverage, reliability as well as connectivity. On coverage target, the study researches on homogeneous sensor network, heterogeneous sensor network, deterministic coverage and random coverage respectively; on reliable target, it researches on the reliability of the network in consideration of the reliability of both sensor nodes and transmission link; on connectivity target, it studies the connectivity in deterministic coverage and random coverage situation respectively.Lastly, a tool in the optimization design of WSN is provided in this study and it offers a visualization support for a dismantling and optimization method of QoS proposed in this thesis so that a detailed disposition plan which meets the needs is put forward in the stage of sensor placement. Moreover, the tool also provides a simulation platform through which the feasibility of the study proposed in this thesis can be tested.