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

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.