湍流大气中高斯谢尔光束的波前位错

Wave Front Dislocations of Gaussian-Shell Beams in a Turbulent Atmosphere

在Rytov近似下,通过引入短期统计平均位错位置的概念,研究了高斯谢尔光束通过近地面弱湍流大气传播时,波前圆形位错形成和位错位置与湍流大气起伏强度和传播距离等参数间的关系.基于湍流大气中平行和交叉双光束的简化近似传输模型,研究了湍流大气中传播高斯谢尔光束波前位错位置与大气湍流强度、传输距离等参数间的相关机制.在远小于光波位相起伏周期的条件下,分别得出了束径不同同轴双光束和交叉双光束传播情况下波前圆位错位置的湍流系综统计平均理论关系.所得结果表明,同轴平行光束干涉和交叉光束干涉所产生的光束波前位错受大气湍流强度、传输距离等参数调制的规律是不同的.

The appearance of wave-front circle edge dislocations and the relationship between the location of the wave-front dislocations of a Gaussian-Shell beam, which was propagating in a weak turbulent atmosphere and in near ground, and the parameters of the turbulent-strength and the distance of propagation had been discussed by the Rytov approximation and the short-term statistical averagingposition of dislocation that was developed in this paper. The relationship between the positions of the wave- front dislocations of the Gaussian-Shell beams propagation in turbulent atmosphere and the atmospheric turbulence strength, the beam propagation distance were analyzed based on a approximation model that the co-axial combined beams and the intersecting combined beams propagated in turbulent atmosphere. The formulas of the statistical average radius of wave-front circle edge dislocations had been developed for the coaxes beams that had different beam diamantes and crossbeams in the cases that the averaging time was shorter than the fluctuation periodic time of wave front. The results show that the dependence of the wave- front dislocations on the parameters of the atmospheric turbulence strength and the beam propagation distance was different,which were caused by the interference of the co-axial beams and the interference of the intersecting beams, respectively.