GPS And Its Pseudolite Augmented Technique For Deformation Monitoring In The Mining Area

In the process of coal mining, the major problems are not only how to mine and exploit coal efficiently, but also how to protect the main building in mining area. Set-ting up the coal pillar suitably is the key technology to solve the above problems. Be-fore that, the high-precision surface movement information of surface observation sta-tions should be measured efficiently, which can be used for studying the parameter change law and serving the mining area developments further. In this dissertation, the relevant issues about mining area surface deformation monitored by Global Position-ing System (GPS) are studied in depth to establish GPS deformation monitoring sys-tem for subsidence surveying in mining area. In order to eliminate the restraining fac-tors of precision, high-precision static GPS baseline solution model and GPS-RTK model with high-precision centering rod are built. Considering that the mining area condition is very complex generally, GPS/Pseudolite integrated system is introduced and an optimal Pseudolites location model is studied. High-Precision integration of GPS/Pseudolites positioning model is built based on the above study. The main re-search achievements and innovation of the dissertation are shown as follow:(1) GPS deformation monitoring mode for subsidence surveying in mining area is proposed. Combining with the productive practice in Suancigou coal mine, Inner Mongolian, basic procedures of the mode and detail process of data processing are presented in order to verify the possibility of high-precision subsidence monitoring in mining area with GPS.(2) GPS baseline solution model based on sequence average method is proposed. Un-modeling system errors such as multipath effect have the low frequency characte-ristic. After introducing the wavelet to eliminate system errors, the final baseline solu-tion can be obtained by sequence average method. The results of the experiment indi-cate that sequence average model not only weakens the influence of multipath effect on baseline solution, but also removes gross error, which increases the procession and reliability of baseline solution.(3) Based on ranging intersection theory and spherical fitting theory, GPS-RTK centering rod measurement method is proposed to improve the efficiency and proces-sion. The main error source is analyzed systematically. The superiority of new method has been verified in theory. The investigation carried out in high-precision test bed has revealed that E direction accuracy and H direction accuracy better than 10mm and N direction accuracy better than 10~30mm can be achieved through only 10s continuous observation by 1hz.(4) An optimal pseudolites location model of GPS/pseudolites integrated relative positioning model is built. The new model is four-dimensional and variables includes time, elevating angle, azimuth and relative dilution of precision (DOP). Compared with the conventional net arrangement scheme, new model is able to guide the pseu-dolites location work more intuitively and efficiently. The measured data has proved that new model is the most optimal theoretically.(5) High-precision integration of GPS/Pseudolites dynamic deformation moni-toring model is proposed. The integrated model improves the positioning precision and reliability by weakening the influence of Pseudolites multipath on integrated po-sitioning. These findings of the research have led the author to the conclusion that high-precision integration of GPS/Pseudolites dynamic deformation monitoring mod-el can weaken the influence of Pseudolites multipath on integrated positioning more efficiently than conventional model, which increases the positioning precision largely.