基于双次回波的LiDAR点云数据滤波方法

LiDAR filtering based on two return pulse

LiDAR系统发射的激光脉冲在遇到不同高度的障碍物时,会返回多次回波,目前大部分系统仅记录首尾两次回波.通常情况下,植被区域局部高程变化明显,而对于道路、房屋屋顶等人工地物,局部高程变化较小;因此,首尾两次回波在这两种不同的地物上具有显著的区别.利用该原理,采用双次回波技术滤除原始LiDAR数据中的植被信息,然后采用传统的形态学滤波区分建筑物和地面脚点,试验表明研究的算法可行有效.

In airborne LiDAR scanner system,laser pulse can be reflected when it meets obstacles with different height.Therefore several pulses will return.Only the first and last ones are generally recorded.In general,the height of vegetation area changes intensely,while for road or construction,the height is coincident.The first and last pulse have great feature on such two objections.The paper makes use of this trait to remove the vegetation.Then traditional filtering algorithms are adopted to divide construction points from ground ones.In the end,a set of LiDAR data is used to test the efficiency of the upward method.