Research And Algorithm Development Of Real-time Deformation Monitoring Technology Based On GPS Single Epoch Calculation

Deformation caused by earthquake, new deposition, sliding of open pit slopes as well as the excavation of undergrounds, tunnels and other underground projects may bring huge threat to the safety of people’s life and property, a number of deformation monitoring and warning systems have been established by governments, organizations and research institutions. While the traditional deformation monitoring technology can’t meet the requirements of most of the projects, how to obtain the real-time deformation information with high precision has always been an issue of the ongoing research.Based on the present situation and development of the domestic and foreign real-time GPS positioning technology, this article focuses on how to directly obtain the deformation of the monitoring stations with the GPS single epoch data and analyze its accuracy. The real-time data of the monitoring station are firstly obtained. Secondly, with the accurate initial baseline vector as constraints, the integer ambiguity is solved. Then the single-epoch model is constructed, after calculating the clock error of satellites and receivers and weakening the tropospheric delay, ionosphere delay and other errors, the coordinates of the monitoring stations will be calculated and their accuracy will be analyzed.The results indicate that:①the deformation accuracy of the monitoring stations are gradually reduced with the increasing of the distance from base stations to the monitoring stations;②when the distances of the base stations and the monitoring stations are about 1 km, the relative deformations between epochs of the monitoring stations are within ±0.2 mm, the cumulative deformations in 48 h of the monitoring stations are no more than ±2 mm;③ the accuracy of the deformation in the vertical direction is lower than the accuracy in the horizontal direction and the horizontal accuracy is about 2 times of the vertical accuracy, which is consistent with the practice;④the statistical analysis shows that the single-epoch deformation accords with normal distribution, therefore, the systematic errors in the model have been greatly weakened and the model is stable.The results provide a theoretical basis for real-time deformation monitoring technology, and it has certain values for the deformation monitoring of the open pit slope and other projects.