Research And Application Of Node Self-Location Technology For Wireless Sensor Network

Wireless sensor network is a multi-hop self-organizing network, composed by a large number of cheap sensor nodes. Its appearance greatly expands the channels for people to get information, transporting the physical information of objective world over a wireless network, passing to people the most direct, effective and truthful information. The applied prospect of wireless sensor network is quite wide, including national defense,environmental monitoring,medical care,precision agriculture and other fields. With the further research and development of Internet of Things, wireless sensor network has becomed the latest hotspot. In wireless sensor network, the locating information is essential to the monitoring activities of sensor network.To determine the location of the incident is the most basic function of sensor network, playing a vital role in improving the applied effectiveness of sensor network.In wireless sensor network, the range-free location algorithms with low-power consumption, low-cost and simple-hardware, are suitable for the large-scale sensor network.DV-Hop algorithm is a range-free location algorithm. In the homosexual and densely distribution network, its positioning accuracy is higher. However, in wireless sensor networks that topology is irregular, traditional DV-Hop algorithm is unreason-able in calculating the average of hop distance, making a great error in node location. To solve this problem, the paper presents an improved algorithm based on topology correlation. The main principle is using topology correlation and the number of hops to weight the average of hop distance,and area-weighting various estimation results, improving the positioning accuracy effectively. Results of the simulation show that the improved algorithm without additional hardware support is more suitable for node localization in random distribution network.With the rapid development of the technology of Internet of Things, this paper applys the technology of Zigbee and location in wireless sensor network into this design of the greenhouse intelligent monitoring system,achieving the intellectual automatic monitoring of greenhouse environment. The system initially realizes real time gathering, processing and display of the environmental data;Transports the monitoring environmental parameters to the computer in monitoring center through the serial port, and accepts the systemic control to generate decision.There are three ways to control,including system automatic control,expert decision-making control and experience automatic control,increasing the flexibility of system control.This system is simple to use,strongly extensible, with a strong practical value...