Opt Express. 2023 Feb 27;31(5):7398-7412. doi: 10.1364/OE.483561.
We demonstrate a continuous-wave (CW) coherent detection lidar (CDL) capable of detecting micro-Doppler (propeller) signatures and acquiring raster-scan images of small unmanned aerial systems/vehicles (UAS/UAV). The system uses a narrow-linewidth 1550 nm CW laser and takes advantage of mature and low-cost fiber-optics components from the telecommunications industry. Using either collimated or focused probe beam geometry, lidar based detection of characteristic periodic motions of drone propellers up to a remote distance of 500 m has been achieved. Furthermore, by raster scanning a focused CDL beam with a galvo-resonant mirror beamscanner, two-dimensional images of flying UAVs up to 70 m range were obtained. Each pixel of the raster-scan images provides both lidar return signal amplitude and target radial speed information. The raster-scan images obtained up to 5 frames per second make it possible to discriminate various UAV types based on their profile and even resolve the presence of payloads. With feasible improvements, the anti-drone lidar is a promising alternative to expensive EO/IR and active SWIR cameras used in counter-UAV systems.
我们展示了一种连续波（CW）相干探测激光雷达（CDL），能够探测微多普勒（螺旋桨）特征，并获取小型无人机系统/飞行器（UAS/UAV）的光栅扫描图像。该系统使用窄线宽 1550nm CW 激光，利用来自电信行业的成熟且低成本的光纤组件。使用准直或聚焦的探测光束几何形状，已经实现了对无人机螺旋桨的特征周期性运动的远距离 500 米的激光雷达探测。此外，通过使用振镜谐振镜光束扫描仪对聚焦 CDL 光束进行光栅扫描，获得了高达 70 米距离的飞行 UAV 的二维图像。光栅扫描图像的每个像素都提供了激光雷达回波信号幅度和目标径向速度信息。每秒可获得多达 5 帧的光栅扫描图像，使得基于其轮廓来区分各种 UAV 类型成为可能，甚至可以分辨出有效负载的存在。通过可行的改进，这种反无人机激光雷达是一种有前途的替代方案，可替代用于反无人机系统的昂贵光电/红外和主动短波红外摄像机。
