Design of a New Multispectral Waveform LiDAR Instrument to Monitor Vegetation

A multispectral full-waveform light detection and ranging (LiDAR) instrument prototype with four wavelengths and a supercontinuum laser as a light source was designed to monitor the fine structure and the biochemical parameters of vegetation. Components of the instrument included a 2-D scanning platform, a supercontinuum laser source, a receiving optical system, and a multichannel full-waveform measurement module. The LiDAR instrument can simultaneously measure multichannel-returned full-waveform laser signals. Position information in the recorded waveform allowed us to compute the distance from the target, whereas the intensity of the signal provided the spectral reflectance. Performance for the measuring distance and the spectrum was evaluated. Experiments indicated that the instrument has high measurement accuracy and has the ability to detect the biochemical characteristics of vegetation via construction of the normalized difference vegetation index and the photochemical reflectance index. The experiment also indicated that the instrument has the potential to generate spectral 3-D point clouds. Therefore, the instrument could play a significant role in detecting the vertical distribution of structural and biochemical characteristics of vegetation.