GPS Elevation Fitting And Accuracy Analysis

GPS height fitting is a hot research field of GPS. Improve GPS positioning precision and accuracy of GPS height conversion, it can get the high precision GPS leveling elevation. The practice has proved according to the actual situation of choosing the correct method of conversion of GPS leveling accuracy can be widely elevation of applied to engineering, deformation monitoring, etc, this will be widened to application field of GPS, really realize the superiority of GPS 3d. Make choice of GPS have better prospect. The paper studies the elevation of GPS system, analyzes the fitting the principle of fitting model, the influence GPS height of the error sources and its correct method, And introduces precision evaluation standard.Thesis discussed the basic principle of elevation measurement .At first it introduces classic level measurement and GPS height measurement. Analyzes the process of GPS height measurement errors caused by the reasons, and precision evaluation standard. Then analyses and discusses the method of transformation of GPS height, which is divided into four types:linear fitting model, plane fitting model, earth gravity model fitting method, the gravity model in combination with GPS leveling. And introduces reference ellipsoid and geodetic height, geoid and orthometric, like the geoid and normal height. After that we discusses in detail the basic principles of BP neural network, and the application in GPS height fitting. Last with BP neural network and the polynomial curve-fitting method of two fitting the same data, contrast results,and analysis precision.