Effects of point density on DEM accuracy of airborne LiDAR

At the request for quick measurement of airborne lidar, the high-density data collected from selected areas was reduced to different percentage of its original density. And the digital elevation models (DEMs) was generated from the ground points extracting from varying point density data sets. Then the correlation between DEMs generated from lower resolution ground data and those from original ground data were analyzed and compared. It is found that point density data set of at least 0.6 points per square meter is necessary to generate an accurate digital elevation model for the test of the measured urban environment. The conclusion is important for quick data acquirement and quick scanning of disaster area after the occurrence of natural disasters.