Simulation of Forest Vegetation Return Waveform for Satellite Large-Footprint LiDAR

Vegetation structure parameters retrieval and forest ecological monitoring based on satellite large-footprint and full-waveform lidar(light detection and ranging) data is a hotspot in recent years. Since vegetation structure parameters and the optical properties have effects on lidar return waveforms, a waveform simulator specified to vegetations for a satellite lidar is established to investigate the influence in detail. The statisticlaw of the spatial vegetation distribution is extracted from field measurements; the parameterized vegetation reflection model is generated by considering the surface roughness and slope, and vegetation canopy reflection characteristics; then, the waveform simulator is developed based on the echo theory for satellite lidars. The simulated waveforms based on the field measurement data in Greater Khingan Mountains and the GLAS echo waveforms have good consistency with R² equal to 0.91. The smaller footprint diameter is beneficial to retrievethe vegetation information that locates at the terrain with a large slope.This research is of reference to the lidar system design for the developingsatellite lidar system of our country.