Reliable Application And Key Techniques Of Wireless Sensor Networks

Wireless Sensor Networks (WSNs), are an entirely new technology which has been sprung up for the last few years. This fire-new computing mode will have a profound influence on many areas in 21st century after the Internet. Although the wireless and sensor technologies have taken a major leap forward, actual applications of WSNs, especially in industrial process control, are still far away. There are no all-purpose system structure and solutions. And many problems have to be studied in practical applications, such as communication reliability, protocol, hardware platform, localization of target, concurrent signal, data compression etc.In the interest of actual deploy and application of WSNs, this dissertation discusses the issues and key techniques about the reliability considering industry as the background. First a prototype for the integration of WSNs and industrial process control has been proposed, and the system solution has been given. Based on the framework, three key issues are studied.1) Communication protocol. Based on the requirement analysis of industrial communication protocol, the mainstream protocols in WSNs are compared, and the ZigBee has been chosen as the best solution of reliable application of WSNs.2) System design of node. Based on the characters of WSNs, system design metrics and structure have been proposed. And the hardware and software design based on ATmega128L and CC2420 have been given.3) Ranging and localization. The techniques based on signal strength and signal speed have been studied. The TOA and TDoA are implemented on mica2 platform, and the performances of these two methods are estimated through experiments. The errors of localization adopting TDoA are analyzed lastly.In conclusion, this dissertation studied several key techniques about reliable application of WSNs. Based on this work, other issues could be discussed further, and the applications of WSNs will be expediently applied to other areas.