A Study On The Trajectory Reconstruction Based On Measured Data

In this paper, trajectory reconstruction techniques was researched based on GPS measured data from the view of trajectory controlling to provide a basis theoretical to improve the projectile firing accuracy in the future.Specific to GPS measurements of exterior ballistics, this magisterial thesis makes a brife represent on the principle and system of GPS measurements, and proceed a error analysis in detail, finally make a simple Introduction for wavelet transform theory and kalman filter theory.The quality of GPS measurement data is to ensure the reliability of trajectory reconstruction. Owning to the effcts have direct relationships with reconstruct precision of exterior ballistics about coping with signals of GPS, this paper adopts wavelet transform and kalman filter to deal with the signals of GPS.The trajectory reconstruction aims to parameter of existing trajectory model using measured data which was processed. Then it extrapolates the impact point by reconstructing of trajectory. At last, it calculates the error of impact point. The thesis presents two ways to reconstructing of trajectory. One is compounding methods based on sole kalman filter (it conducts optimal estimation of the trajectory parameters using kalman filter directly). The other is wavelet transform and kalman filter together (first it removes fixed error using wavelet theory. Then, it denoised. At last, it conducts optimal estimation of the trajectory parameters using kalman filter). The result of simulation indicates that the latter has higher degree of accuracy. It has great significance in the practical application.At last, the simulation takes the 155 mm projectile for example. the thesis carries two ways out to make the full trajectory simulation. The result shows that, the range and following points of GPS have a certain impact. The accuracy of reconstruction goes down along with the range increasing. Also, it makes reasonable definition of the following points of GPS.