超高斯贝塞尔光束在湍流大气中的传播

Propagation of SGB beam in turbulent atmosphere

针对激光束在大气中传播时,大气湍流引起的光强起伏等现象限制光束实际应用的问题,研究了消除或者减小大气湍流对光束质量影响的方法。基于广义惠更斯菲涅耳原理,通过数值模拟研究了超高斯贝塞尔(SGB)光束在不同湍流强度下的轴向和横向光强分布。针对SGB光束在一定传播距离上具有无衍射性和自恢复性能的研究发现,在弱湍流大气环境中,尽管湍流强度的增大会加速轴上光强的衰减,但是在一定距离范围内,SGB光束仍然保持其无衍射特点。在弱湍流强度变化范围内,通过选择合适的孔径函数,可以将SGB光束的横向光强分布的峰值变化限制在不超过10%,表明SGB光束具有一定的抵制大气湍流干扰的能力。

Applications of laser beams to wireless communications are limited by the light intensity fluctuation caused by atmospheric turbulence when they propagate the atmosphere. In order to find out an approach to remove or decrease the effect of atmospheric turbulence on the beam quality, the axial and transverse light intensity distribution of the Super-Gaussian-Bessel （SGB） beam is investigated by means of a numeric simulation based on the general Huygens-Fresnel principle. As the SGB beam is characterized by its non-diffracting and self-reconstruction abilities over a certain propagation distance, it is proved that the axial intensity of the SGB beam is decreased under the influence of atmospheric turbulence, but its non-diffraction characteristics are still maintained over a certain propagation distance in the weak fluctuation. The peak intensity variation of the transverse intensity distribution of the SGB beam can be kept below 10 percent by selecting a proper aperture function in the range of weak fluctuation. These results show that the SGB beam has the ability to resist the influence of atmospheric turbulence.