部分相干双曲余弦高斯阵列光束的湍流距离

Turbulence Distance of Partially Coherent Cosh-Gaussian Array Beams

基于广义惠更斯-菲涅耳原理,采用Rytov相位结构函数二次近似和积分变换技术,推导出了部分相干双曲余弦高斯(ChG)阵列光束通过大气湍流传输时光束湍流距离的表达式。研究结果表明,部分相干ChG阵列光束的湍流距离与大气湍流强度、光束参数(包括子光束数、光束相干参数、离心参数、相对子光束间距)以及光束叠加方式(即交叉谱密度函数叠加和光强叠加)等有关。部分相干ChG阵列光束的光束扩展会随着大气湍流强度的增大而增大,但当选择合适的光束参数以及光束叠加方式时,可以减小湍流对部分相干ChG阵列光束扩展的影响。

Based on the extended Huygens-Fresnel principle,the expression for the turbulence distance of partially coherent cosh-Gaussian（ChG） array beams propagating through atmospheric turbulence is derived by using the quadratic approximation of Rytov′s phase structure function and the integral transform technique.It is showed that the turbulence distance depends on the atmospheric turbulence intensity,the beam parameters（i.e.,the beam number,the beam coherence parameter,the decentered parameter,the relative separation distance of beams）,the type of the beam superposition（i.e.,the superposition of the cross-spectral density function and the superposition of the intensity） and so on.It is also showed that the turbulence distance of the partially coherent ChG array beams will increase with the atmospheric turbulence intensity,but the effect of turbulence on the spreading of partially coherent ChG array beams can be reduced by choosing the suitable beam parameters and the suitable type of the beam superposition.