基于DEM与可见光图像的机载激光成像雷达强度像仿真

激光成像雷达由于能获取目标的距离信息,因而在飞行器制导、避障、机器人导航等方面有广泛的应用前景.这里的研究目的是根据激光成像雷达成像原理进行雷达反射强度像的仿真.在仿真过程中,首先讨论激光成像雷达的强度成像方程,然后分析机载激光成像雷达的扫描成像模型.由机载激光成像雷达扫描成像模型与数字高程模型(DEM)获取成像几何关系,由与高程图配准好的可见光图像来获取目标地物的反射特性,从而获得仿真的激光雷达反射强度像;由于激光在大气中传输时不可避免地要损失,在仿真计算中考虑到激光在大气中传输时大气对激光的消光系数,因而使仿真更加逼近客观实际成像结果.从仿真的反射强度图像看,结果很理想.仿真的强度图像成功地用于激光成像雷达强度像与可见光图像的匹配导航中.

Simulation of Intensity Image of Airborne-based Imaging Laser Radar Based on DEM and Visible Image

Image laser radar has tremendous potential applications such as aircraft navigation, obstacle avoiding and robot navigation because it can obtain both distance information and intensity information from object. Herein, the intensity image of imaging laser radar is simulated according to the principle of imaging laser radar. In the simulation, the equation of imaging laser radar is firstly discussed. Next, scan mode of airborne-based imaging laser radar is presented. Geometrical relation is calculated according to scan mode of airborne-based imaging laser radar and digital elevation model (DEM) data. On the other hand, the reflectance of object is obtained using the visible-band image registered to the DEM image. Because when the laser is transmitted in the atmosphere, thus the attenuation of laser is unavoidable. In the simulation, in order to acquire more accurate result, the attenuation coefficient of the laser is considered during the laser is transmitted among the atmosphere. According to the experimental result using real terrain data, the simulation result is satisfactory. The result intensity images are used successfully in navigation.