Airborne three-wavelength LiDAR system

This study proposes a three-wavelength linear and single-photon composite detection LiDAR system to meet the development requirements of medium-and high-altitude airborne multiwavelength LiDAR for high-resolution three-dimensional imaging of the ground, as well as to achieve the goal of spectral and land-water integrated detection. The three-wavelength array beam illumination combined with Fresnel prism cone scanning mode is used to realize the rapid multiwavelength three-dimensional imaging of the airborne platform. This study introduces the details of a three-wavelength laser light source module, Fresnel prism beam scanning module, multiwavelength coaxial transceiver optical system, and linear and single-photon composite detection, acquisition, data processing, and so on, based on the system’s operating concept. The multiwavelength laser common aperture transceiver, synchronous acquisition, processing, and storage assure the integrity and consistency of spectral and spatial geometric data in space and time and then provide data support for multiwavelength data fusion and land-water integrated detection. To test and assess the performance of an airborne three-wavelength LiDAR, a system static test was performed first, followed by a static ranging test on a 3.6 km target was completed. The ground dynamic test was then performed, and the system’s software and hardware were tested. The imaging data were basically consistent with that of commercial LiDAR. Finally, the airborne flight test was performed, and the three-wavelength 3D imaging was completed in cities, industrial areas, hills, reservoirs, and other areas. The land-water integrated detection and the fusion of three-wavelength linear and single-photon data in spectral and spatial dimensions are preliminarily realized.