Research On Ecolution Charateristics Wireless Sensor Networks

Wireless sensor networks (WSNs) is a multi-hop and self-organizing network applications system, with a large number of densely deployed nodes in the control region of homogeneous or heterogeneous micro sensor with sensing, computing and wireless communicating capabilities, nodes monitoring events and data collection in the physical region through collaboration, and sending the information to the observer. It is an evolution of complex system,contains a large number of nodes and links, with many intricate variables. On the basis of the characteristics of wireless sensor networks and complex network theory in-depth analysis, an expansion of cellular automaton model for wireless sensor networks is constructed in this article, and the mapping relationship between the space configuration and the characteristics is seted up. From the perspective of evolution, this article analyzes and describes the sleep scheduling mechanism, critical connectivity, degree and degree distribution, clustering coefficient and average path length and other self-organization phenomena and statistical characteristics of wireless sensor networks.The main work of the research is in the followings:(1) To simulate the sleep scheduling mechanism PEAS(Probing Environment and Adaptive Sensing) algorithm based on the environmental detection, using one dimensional cellular automaton. This article analyzes the overall network behavior under the algorithm from the geometry of evolution and cellular activity and notes the need for asynchronous wake-up and increase the status updates excitement, and improves the algorithm.(2) To research the critical connectivity of randomly deployed wireless sensor networks using the expansion of two dimensional cellular automaton model, the relationship of nodes and critical communication radius is dealed with, and the network reliability is analyzed. The network critical connectivity state has a complex evolutionary behavior, such as network connectivity0-1step, the trends of the statistical characteristics in the critical connectivity state. The existing research on the network connectivity and the statistical characteristics is usually based on the homogeneous networks. Particularly, the effect of the small number of heterogeneous nodes on the network connectivity and the statistical characteristics is studyed comparing with that to homogeneous networks.(3) This article attempts to put forward a layout optimization of heterogeneous nodes from the point of energy savings, respectively, based on the WS model and the NW model, wireless sensor networks with small-world effect are structured, from the network nodes degree, connectivity, the optimal cluster number and data flow aspects to layout optimization goals. The simulation result shows that the algorithm can significantly reduce the average path length remain the degree of network nodes in the ideal range, increas the clustering coefficient and the thronghput. At the same time, using the re-connected effect with heterogeneous nodes to reduce the transmit power of the common nodes, significantly save the totle energy consumption of the network both from a single node and the whole network, the introduction of heterogeneous nodes has a good performance.The related research can be the thinking and reference for deployment and topology control in wireless sensor networks, the topology structure will be optimized and the entirety performance will be improved of wireless sensor networks along with this work.