目标反射特性对激光测距的影响

针对非合作小目标激光测距系统,目标表面的反射特征对激光回波信号有很大的影响。建立测量表面双向反射分布函数(BRDF)的装置,对常用的两种热控材料——白漆涂层和F36多包层,测量了其在1064 nm波长下的双向反射分布函数。得出了白漆涂层镜面反射很小,散射角较大,利于各方向接收回波信号;而F36多包层镜面反射很强,散射角-2°~2°,不利于探测。通过由表面BRDF与由朗伯散射计算得到的最小接收功率的比较,得出了入射角大于45°入射白漆涂层时,回波信号较小;大于2°入射F36多包层时,没有回波信号。

For a laser range finder to measure the smallest non-cooperative target, the reflective characteristics of the target surface are significant for echoed signal. A experimental setup to measure the bidirectional reflection distribution (BRDF) of the surface is developed. The BRDF functions of white-painting coating and F36 cladding heating reflective materials at 1064 nm are obtained. The results show that the white-painting coating has small specular reflection and large scattering angle, it is better for laser range finder. While, the specular reflection of F36 material is too magnitude, and the scattering angle is only -2°-2° The echoed signal of laser rangefinder will be great fluctuation with the incident angle. Through comparing the minimal receiving power obtained by BRDF and Lambertian diffuse reflection, the echoed signal is very small, when the incident angle is larger than 45° and 2° for white-painting coating and F36 cladding, respectively.