Laser scattering properties of the rough ellipsoidal object with the random facet model

摘要

Laser scattering properties are studied from the rough surface of an ellipsoidal object with the random facet model and the electromagnetic scattering theory. For actual ellipsoidal objects, such as some airships and air balloons, their lateral correlation lengths are usually longer than the incident laser wavelength 1.06μm, and their surfaces are conventionally the Lambertian surface. Hence, it is feasible to analyze their laser scattering properties of the ellipsoidal object by means of the random facet model. In order to evaluate the scattering, firstly, the ellipsoidal surface is decomposed into many facets according to axial symmetry, then scattered intensity can be denoted for every facet with a laser scattering model of the Lambertian surface. Secondly, total intensity received by a far-field optical detective system is gained with the incoherent superposition principle for all facets, where an incident shadow function and a scattering shadow function are introduced. In the end, far-field angular distribution of the laser scattering intensity is computed and analyzed under different conditions. The numerical results suggest that the laser backscattering intensity of the ellipsoidal object increases with its surface roughness. However, if the ellipsoidal surface is correspondingly rough, the incident laser power might be scattered around.