The Design And Implementation Of Wi-Fi Signal Evaluation And Mesurement System In The Mine Confined Spaces

Wi-Fi is a brand originally licensed by the Wi-Fi Alliance to describe the underlying technology of wireless local area networks(WLAN) based on the IEEE802.11specifications. Wi-Fi technology has been widely applied because of being integrated with existing wired Ethernet easily and low-cost networking."Wireless city" has being constructed and operated in China.With the development of wireless communication technology, corresponding to the requirements of the national coal security and informatization,wireless communication technology has being used in the mine,which is regarded as a major breakthrough of the wireless communications technology.Wi-Fi can meet the bandwidth requirement of building mine communications network. However, the coal mine laneway become a complex, multi-change, special signal propagation area owing to many constraint Factors,such as electromagnetic waves fading, the impact of noise and multipath effects.The building of Wi-Fi network in the mine and evaluating signal is a serious challenge.The measurement and evaluation of Wi-Fi signal has being accomplished by using common WLAN network Tester without the dedicated equipments in the mine.It is very difficult to build the Wi-Fi wireless network and find the black spots in the mine.Lack of scientific evaluation standard,the acceptance of Wi-Fi engineering has not been completed efficiently.Based on a deep study of the relevant regulations of the mine wireless communication, the characteristics of wireless signal propagation in the confined spaces of the mine and the Wi-Fi wireless network technology,the design and implementation scheme of the mine confined spaces Wi-Fi signal evaluation system has been proposed in this paper,composed by the dedicated embedded Wi-Fi module, the spectrum analyzer,the airpcap wireless network card and the portable terminal device.The dedicated embedded Wi-Fi module is used to get active AP parameters, such as the MAC address, SSID, channel, type, signal strength, signal-to-noise ratio and channel capacity. The spectrum analyzer has applied to the wireless communications environment interference analysis.The portable terminal software through the embedded Wi-Fi module,the Airpcap and the spectrum analyzer to obtain the data for analysis,display and storage.In accordance with the relevant regulations and requirements of the mine wireless communication,the assessment report combined with the mine map will be generated quickly.After the actual test,the measurement and evaluation system of Wi-Fi signal in mine confined spaces can measure and evaluate Wi-Fi signal accurately,objectively and efficiently.