激光跟踪中目标卫星表面BRDF对回波信号的影响

The bidirectional reflection distribution of target satellite surface with different roughness was simulated by the formula of the bidirectional reflection distribution function(BRDF) in laser tracking in the space. The component of diffuse reflection became larger and the component of specular reflection became smaller with the increase of the target surface roughness. Meanwhile, the scattering angle became larger. These benefited the random receiving direction and decreased the sensitivity of receiving direction. The varieties of BRDF of target satellite surface affected by the change of the incident angle were also simulated. The change of bidirectional reflection distribution was obtained. The receiving echo increased with the increase of the component of specular reflection, when the incident angle was small and the illumination beam axis and receiving telescope axis were coaxial. The receiving echo power decreased quickly with the increase of the incident angle. When the incident angle was larger than 34, the minimum receiving echo power computed by BRDF was lower than the one computed by the formula of lidar supposing that the target satellite surface was Lambertian reflection plate. The illuminating laser power should become 5 times the former one or the receiving aperture became 2.5 times the former one. These methods could remove the effect of the decrease of the receiving echo power.