The Comparison of Denoising Methods for Photon Counting Laser Altimeter Data

The space-borne earth observation LiDAR satellite Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) equipped with photon counting LiDAR system was launched on September 15, 2018. Significantly different from waveform laser altimeter carried on ICESat, the multiple beams photon counting laser altimeter can better measure Earth’ surface and directly provide the location of the scattering event. Due to the high sensitivity, the photon detector responds photons come from the solar background and the atmospheric scattering, which causes plenty of noise. It is necessary to study an effective method to identify signal photons from noise. This paper aims to study serval typical noise filtering methods and discuss their characteristics. The experiments are conducted on both ice sheet and vegetation data sets. The results are presented and some suggestions for choosing which denoising method to face in different environmental conditions are given.