Analysis of backscattering characteristics of objects for remote laser voice acquisition

This study is focused on numerical simulation analysis and experimental study regarding the influence of backscattering characteristics of objects for long-range laser voice acquisition. Based on theoretical analysis, three parameters, including surface roughness of an object, incident angle, and refractive index, which will influence the performance of remote scattered reflection laser interference voice acquisition, are investigated and analyzed. After analysis and simulation, an experimental system is set up to demonstrate the influence of backscattering characteristics of an object. The results show that the restored amplitude of a voice signal decreases gradually, corresponding to an increase of surface roughness from 0.4 to 12.5 μm; the incident angle of the measured laser shall reside between 57.32 deg (1 rad) and -57.32  deg (-1  rad); the optimal incident angle is 0 deg for all kinds of objects; and the metal object is a better choice of material selection. In addition, the restored amplitude of a voice signal rises with the attenuation coefficient of metal increasing. It also increases with the refractive index for a nonmetallic object. Comparing a metal to a nonmetallic object, the amplitude of voice signal varies significantly.