Research On Wireless Communication And Personnel Positioning Technology In Mine

China is rich in mineral resources,which provide endless resources for industrial production.However,it still lags behind some developed countries in terms of mining methods and safety precautions.As the country attaches great importance to safe production,the State Council has put forward the strategic guideline of "saving,cleaning and safety".More and more research has been put into the development of downhole equipment,and more and more modern equipment has been put into downhole production.At present,the equipment used in downhole is mostly based on RFID and computer network,which requires laying cable.Once the cable is damaged,it will cause the failure of the equipment.In view of the above problems,this paper adopts ZigBee technology as the core of wireless communication technology to design a set of wireless communication and positioning system,which does not need to lay a cable and can dispatch and search and rescue underground personnel in the case of failure of wired communication.This paper mainly studies from the following aspects:1.This paper introduces the basic principles of ZigBee network,including types of devices,network topology,etc.and analyzes some common technologies for ZigBee wireless network positioning,distance-based positioning technology,and distance-free positioning technology.Based on the consideration of cost,difficulty and accuracy,positioning based on RSSI is selected.2.By deducing the log-normal shadowing model,the mathematical relation model between RSSI and propagation distance is obtained.Based on the measured data,the minimum residual sum of squares is taken as the standard to create function,and the model parameters are obtained by solve function.Then the distance measurement model is trained by BP neural network.The model accuracy of the two methods is compared.Based on the model,the maximum likelihood algorithm and particle swarm optimization algorithm are used to locate the nodes,and the positioning accuracy of the two methods is compared.3.The hardware circuit is designed and debugged and IAR development tools were used to complete the program development of ZigBee devices with different nodes,and Visual Studio tools were used to complete the development of upper computer software to realize the communication with devices,topology display and positioning results display.4.Finally,in the laboratory environment,the system was tested in two different scenarios: open field and narrow passage,and the communication function and positioning function of the system were verified.