Research On Clustering Based Routing Energy-Saving Technology For Wireless Sensor Network

Recent advances in sensor technology, low-power electronics, and low-power radio frequency design have enabled the development of inexpensive and low-power wireless sensors that can be connected via a wireless network. Wireless sensor network (WSN) is an intelligent autonomous measure and control system that can complete given missions, which made up bestrewing many small nodes that have communication and calculate ability to non-person watch areas. Wireless sensor network, which is made by the convergence of sensor, embedded computing, distributed information processing and wireless communication technologies, is a new information acquisition, processing and transmission technologies. Its random bestrewing, self-organizing, and environment adapting make it widely used in military, environment, medical care, home and other commercial areas, which arises the highlight in industrial and academic areas.The study of clustering routing protocol for WSN is the main part of this dissertation. The number of sensor nodes in WSN is numerous and single node is extraordinarily limited in resource. The most significant aim of designing routing protocol of WSN is to reduce the overall energy dissipated in the network and to maximize the network lifetime. This dissertation focuses on the routing protocol for wireless sensor network and its energy-saving optimization and has some research on following aspects:Firstly, we summed up the development history, concept, structure, characteristics of WSN and analyzed the key technical issues and network protocols of WSN,we studied the network protocols of WSN and routing protocols on the classification system. We analyzed and compared some classic routing protocols like flooding, classified protocol and date-centered protocol from their advantages and disadvantages.Secondly, we chose LEACH routing protocol as the research target. We analyzed its insufficient. Based on the original algorithm, we put forward their improvement projects. Due to its random selection of clusters, the traditional LEACH protocol definitely results in the unbalanced state of nodes'energy, which shortens the whole network lifetime and decreases the system throughput, a clustering algorithm based on adaptive abdication strategy was proposed in this dissertation. By setting an energy threshold to evaluate the healthiness of clusters, the algorism enables those dying clusters to pass their status to the suitable successor according to an abdication strategy, which ensures the reliability of data transfer. This algorithm brings about a longer network lifetime and a larger throughput compared with LEACH.Thirdly, since wireless sensor network has a closer relationship with physical communication environment than other network, and its specific transmission condition is complex and dynamic, in order to effectively save energy and ensure the transmission reliability, the design of routing algorithm for WSN need to take the physical communication environment into consideration, such as the irregularity of radio frequency, the fading of multi-paths and so on. Therefore, it is a practical way to combine the physical layer with routing algorithm to ensure and enhance the network quality and efficiency. We introduced the mature technology of Multiple Input Multiple Output (MIMO) into wireless sensor network which is composed of nodes with single antenna, substituting selectively the conventional Single Input Single Output (SISO). After taking into account the transmission and circuit energy together, the appropriate application scenarios of both MIMO and SISO are derived, and then a corporative MIMO strategy based on clustering is proposed. Taking the merits of both transmission modes, the strategy reaches an optimal result in respect of energy consumption. Meanwhile, the algorithm distributes the energy consumption of cluster head to corporative nodes, thus even balance the load and prolong the network lifetime.Fourthly, the algorithm proposed in this dissertation is simulated in NS2 simulation platform. According to the analysis and comparison, it reveals that the proposed adaptive abdication strategy and Virtual MIMO Algorithm can effectively prolong network lifetime and realize the energy saving target.Last, the whole work of the dissertation is outlined and the further research issues are discussed.