Research And Implementation Of GNSS Mine Subsidence Monitoring System Based On QIANXUN Location Service

Mine subsidence monitoring market has high demand for low-cost,high-precision and high-efficiency monitoring methods,which is also the main development direction of such products in the future.In view of the high accuracy and efficiency of the rapid static positioning technology,but due to its accuracy does not meet the requirements of subsidence monitoring and the limitations of complex operation,This paper optimizes the rapid static positioning technology in the aspect of random model,combined with real-time data communication and QIANXUN precise space-time service.The GNSS mining subsidence monitoring system is completed.The main work and achievements are summarized as follows:(1)This paper introduces the GNSS relative positioning model and related theories,including the principle of GNSS relative positioning,three common prior random models and a posteriori combined positioning random model,as well as three commonly used GNSS parameter estimation methods.(2)This paper introduces the practical requirements and technical principles of rapid static positioning technology,puts forward a combined random model of satellite altitude angle Helmert considering PDOP,applies it to the rapid static positioning technology,and tests its accuracy with the measured data.The experimental results show that the new combined random model can effectively improve the accuracy of static positioning,and the observation time is more than 5 minutes,which can meet the accuracy requirements of mine subsidence monitoring.(3)This paper studies the transmission protocol and data format of real-time data communication,develops GNSS real-time data transmission and decoding program,completes the data transmission based on TCP client and Ntrip protocol and data decoding based on rtcm3.2 format,and realizes GNSS real-time data communication.(4)Based on the real-time data communication,the service is applied to fast static positioning.The experimental results show that the fast static performance of the method combined with QIANXUN service is reduced,but the observation time of more than 5 minutes can still meet the needs of mine subsidence monitoring,and the efficiency is greatly improved.(5)This paper expounds the research idea of GNSS mine subsidence monitoring system,designs a low-cost GNSS data acquisition terminal,constructs a real-time data communication system,and completes the deployment of user software centered on the fast static positioning technology with the combination of stochastic model and QIANXUN service.With the application of the production scheme of the system,a low-cost,high-precision and high-efficiency GNSS mine is realized Subsidence monitoring.