Wavelength selection of dual-mechanism LiDAR with reflection and fluorescence spectra for plant detection.

Abstract

With the continuous expansion and refinement in plant detection range, reflection, and fluorescence spectra present great research potentials and commercial values. Referring technical advantages with hyperspectral and fluorescence lidar for monitoring plants, the synchronous observation with reflection and fluorescence signals achieved by one lidar system has attracted wide attention. This paper plans to design and construct a dual-mechanism lidar system that can obtain spatial information, reflection, and fluorescence signals simultaneously. How to select the optimal detected bands to the dual-mechanism lidar system for monitoring plants is an essential step. Therefore, this paper proposes a two-step wavelength selection method to determine the optimal bands combination by considering the spectral characteristic of reflection and fluorescence signals themselves, and the hardware performance of lidar units comprehensively. The optimal bands combination of 4 reflection bands of 481 nm, 541 nm, 711.5 nm, 775.5 nm, and 2 fluorescence bands of 686.5 nm, 737 nm was determined. Besides, compared with the original reflection or fluorescence bands, the overall accuracy and average accuracy of the optimal band combination were respectively improved by 2.51%, 15.45%, and 7.8%, 29.06%. The study demonstrated the reliability and availability of the two-step wavelength selection method, and can provide references for dual-mechanism lidar system construction.