Data simulation of an airborne LIDAR system

An airborne LIDAR (LIght Detection And Ranging) system can rapidly generate 3D points by densely sampling the terrain surfaces using laser pulses. The LIDAR points can be efficiently utilized for automatic reconstruction of 3D models of the objects on the terrain and the terrain itself. The data simulation of such a LIDAR system is significantly useful not only to design an optimal sensor for a specific application but also to assess data processing algorithms with various kinds of test data. In this study, we thus attempted to develop data simulation software of an airborne LIDAR system generally consisting of a GPS, an IMU and a laser scanner. We focused particularly on the geometric modeling of the sensors and the object modeling of the targets and background. Hence the data simulation software has been developed using these models. For the geometric modeling, we derived the sensor equation by modeling not only the geometric relationships between the three modules, such as a GPS, an IMU and a laser scanner but also the systematic errors associated with them. Moreover, for rapid and effective simulation, we designed the data model for both targets and background. We constructed the model data by converting the VRML formatted data into the designed model and stored these data in a 3D spatial database that can offer more effective 3D spatial indexing and query processing. Finally, we developed a program that generates simulated data along with the system parameters of a sensor, a terrain model and its trajectories over the model given.