影响机载激光扫描测高精度的系统误差分析

Analysis of Systematic Error Influencing the Accuracy of Airborne Laser Scanning Altimetry

简要介绍了机载激光扫描测高技术的系统组成和发展现状。通过坐标转换技术建立起机载激光扫描对地定位的基本几何关系 ,并从这些几何关系出发 ,着重分析了动态偏心改正及动态时效误差对机载激光测高精度的影响 ,对不同的误差源如何影响定位结果的精度进行了讨论 ,最后给出模拟计算结果 ,得出了一些有益的结论。

In this paper the error sources related to the laser instrument,GPS,and INS are analyzed in details.Several coordinate systems used in airborne laser scanning are set up,and then thebasic formula of the system is given.This paper emphasizes on discussing the kinematic offset correction between GPS antenna phase center and laser pulse fired point.And kinematic time delay influence on laser footprint position,the ranging errors,positioning errors,attitude errors and inte_gration errors of the system are also explored.Finally,the result shows that the kinmatic time delay can be neglected in comparison with other errors.The accuracy of the coordinates is not only influenced by the amplitude of the error,but also controlled by the flight height,scanning angle amplitude and attitude magnitude.