根据广义Huygens—Fresnel原理和修正von Karman谱模型,推导出了径向分布高斯阵列光束经非相干合成后在大气湍流中传输时的光强分布解析表达式,并对阵列光束自耦合特性随传输距离和径向分布半径的变化情况进行了数值分析,最后对径向分布半径不同的阵列光束自耦合特性随传输距离的变化进行了测量。实验结果表明:高斯阵列光束在大气湍流中水平传输时,随着传输距离的增加阵列光束会从某一距离处耦合成一束,且合成光束的平均光强呈类高斯分布;相同传输条件下,径向分布半径越小,阵列光束的自耦合特性越好。
Based on the generalized Huygens-Fresnel principle and the modified von Karman spectrum model, the analytic expressions for intensity distribution of radial Gaussian array beams after incoherent combination that propagation in the atmospheric turbulence were derived. And the self-coupling characteristics of array beams was analyzed numerically with the change of transmission distance and the radial radius. Finally self-coupling characteristics of array beam of different radial radius with the change of the transmission distance had been measured by using a beam analyzer. The experimental results show that when Gaussian array beams propagate in atmospheric turbulence horizontaly, array beam will combine a beam from a certain distance with the increasing of transmission distance. And the average intensity of the combined beam is like-Gaussian distribution; under the same transmission conditions, the smaller the radial radius, the better the serf-coupling characteristics of the array beams is.