Research On Kalman Filtering Algorithm And GPS Carrier Phase Difference Positioning On Landslide Deformation Monitoring

In view of the proposed requirements by landslide deformation monitoring for GPS precise positioning, this paper has studied and designed the model of GPS carrier phase difference positioning and kalman filtering algorithm according to the landslide deformation monitoring based on clear exposition of GPS positioning principle, positioning error causes and kalman filtering algorithm and also has made tight mathematical derivation and simulation experiments on computer.Through the comparative analysis of different locating ways, this paper has explained the rationality of choosing this locating mode of single reference station carrier phase difference. And the rationality of choosing differential positioning to reduce the positioning error and kalman filter to improve positioning accuracy has been explained through the analysis of the influence of errors on positioning accuracy.This paper designed the mathematical model of double differential carrier-phase and the model of kalman filter. By using single phase of carrier phase, the influence on satellite clock errors and ephemeris errors have been eliminated and the influence on ionospheric delay and tropospheric delay have been reduced. By using the two difference of carrier phase, the influence on clock errors of receiver at monitoring point has been further eliminated based on eliminating satellite clock errors, and the number of the unknown has been reduced as well. During the process of double differences of carrier phase, the elimination of the influence on double difference ambiguities of carrier phase has succeeded by eliminating the model that integer ambiguity of double differences of carrier phase uses. Using the model of kalman filter, the reduction of the influence on disturbance noise and measurement noise has been realized. This paper used the coordinates of the correction value solved by carrier phase second difference and kalman filtering to modify the location of monitoring points coordinates, by sampling coordinate correction value solved to correct the general coordinates of monitoring points to verify the reliability of the method. In sum, this paper effectively improved positioning accuracy, and provided realization algorithm of positioning accuracy by computer simulations and experiments. The data of experimental results in this paper has verified the feasibility and effectiveness of the algorithm.In this paper, effective theoretical research and simulated experiments have been made in order to improve GPS locating accuracy to meet the requirements of the application of landslide deformation monitoring and forecasting.