Research On ZigBee Network Simulation Technology Of Urban Drainage System

ZigBee is an emerging wireless network technology which has some characteristics, such as short distance of transmission, low data rate, low cost and low power consumption. ZigBee is highly suitable for many application fields, such as industrial control, automotive automation, automatic control of agriculture, medical equipment, etc. This paper mainly study on the tasks of system modeling and simulation with OPNET for ZigBee-based wireless sensor network of urban drainage network monitoring system and then find out the factors that affect the network performance to make reasonable guidance and advice to supervision of urban drainage network.This paper introduces the urban drainage system and the status of its management, summarizing the ZigBee technology and basic knowledge of WSN, analyzing and comparing the existing several network simulation software, studying the principles of OPENT and the mechanism of triple-layer modeling in it. Finally, establishing a simulation model of a ZigBee network. On the base of simulation model of ZigBee WSN for urban drainage network monitoring system, this paper designed four experiments to study the factors that affect the ZigBee-based WSN performance, which are network topology, network node size, node transmission power and network load. Then, the experiments data and curves had obtained, such as MAC layer packets, end to end delay, packet loss rate, packets delay in application layer.The experiment data and curves had shown: firstly, network topology and nodes transmitting power has little affect on the WSN and would not affect the normal transmission; secondly, it leaded the end to end packet delay from 0.008s to 0.16s in MAC layer when the experiment added 12 nodes in network of 14 nodes, which had shown that the increase of nodes would made network performance deteriorated; thirdly, the results of the same data with the same rate in application layer created by the 10 router nodes and terminal nodes were that end to end delay of data packets in MAC layer sharply increased from 0.01s to 0.36s. Thus, the paper concluded that the major factors affecting on the performance of ZigBee-based WSN were nodes number and network loads.This paper mainly study on the ZigBee-based WSN of urban drainage network monitoring system. The research results not only provide scientific guidance and advice to the building of urban drainage network monitoring system, but also provide simulation support for ZigBee-based WSN implementation and performance analysis.