A Quantitative Assessment of LIDAR Data Accuracy

Airborne laser scanning sensors are impressive in their ability to collect a large number of topographic points in three dimensions in a very short time thus providing a high-resolution depiction of complex objects in the scanned areas. The quality of any final product naturally depends on the original data and the methods of generating it. Thus, the quality of the data should be evaluated before assessing any of its products. In this research, a detailed evaluation of a LIDAR system is presented, and the quality of the LIDAR data is quantified. This area has been under-emphasized in much of the published work on the applications of airborne laser scanning data. The evaluation is done by field surveying. The results address both the planimetric and the height accuracy of the LIDAR data. The average discrepancy of the LIDAR elevations from the surveyed study area is 0.12 m. In general, the RMSE of the horizontal offsets is approximately 0.50 m. Both relative and absolute height discrepancies of the LIDAR data have two components of variation. The first component is a random short-period variation while the second component has a less significant frequency and depends on the biases in the geo-positioning system.

Automated summary

Airborne laser scanning sensors can collect a large number of 3D topographic points quickly, providing high-resolution depictions of complex objects. This research presents a detailed evaluation of LIDAR system and quantifies the quality of LIDAR data, an aspect often overlooked in published studies. Field surveying is used to evaluate the planimetric and height accuracy of the LIDAR data. The average elevation discrepancy is 0.12 m, and the RMSE of horizontal offsets is approximately 0.50 m. The height discrepancies have both random short-period variations and biases from the geo-positioning system.