Land Cover Characteristics of Airborne LiDAR Intensity Data: A Case Study

Airborne Light Detection and Ranging (LiDAR) systems provide precise geometric information over the surface of the Earth, as well as radiometric information. Studies on LiDAR have primarily focused on topographic mapping and urban 3-D modeling. The radiometric characteristics of backscattered laser intensity are meanwhile not yet clearly understood. Recently, the interest in the radiometric properties of LiDAR has been rapidly expanding, and several works have performed the normalization or correction of laser intensity data. However, the effect of radiometric correction is still unclear, and a suitable radiometric correction method has yet to be proposed. This letter investigated the radiometric properties of LiDAR intensity data as a prerequisite procedure for the practical use of intensity. On the basis of a comparison with the surface reflectance measured by a portable spectroradiometer, it was found that the LiDAR intensity of vegetation was unusual. For land cover types other than vegetation, it was observed that range distance was the dominant factor of the intensity of LiDAR. Therefore, this letter suggests that the correction of LiDAR intensity in terms of range is effective to the land cover types except vegetation.