Effects of target reflective characteristics on laser ranging by comparing the BRDF model with the Lambertian model

During the process of laser ranging, the interaction between the target and the laser beam has the close relationship with the light scattering characteristic of the target surface, which can be characterized by the bidirectional reflectivity distribution function (BRDF). This paper discusses the effects of target reflective characteristics by the BRDF model and the Lambertian model. The BRDF is definited by surface parameters, such as surface roughness, correlation lengths and refractive index, incident angle and wavelength, which the Lambertian model does not include the detailed properties of the target. The results show BRDF is more precise than Lambertian model in factual environment. The main work is the research on calculating and comparing the minimal detectable power of laser rangefinder obtained the two models under different incident angles and surface roughness. The angular dependence of the BRDF is related to the microscopic properties of the surface. It showS that when the surface roughness increases the detectable power decreases rapidly. Modeling and simulation of the typical target shape of parabolic is provided in this paper on the bases of the BRDF and the LRCS is calculated. According the above study, it will provide some fruitful reference for further parameters choice of laser rangefinders and laser radar.