部分相干高斯-谢尔光束在大气湍流中的展宽与漂移

Spreading and wander of Gaussian-Schell model beam propagation through atmospheric turbulence

基于广义惠更斯-菲涅耳原理,交叉密度函数以及Rytov's相位结构函数二次近似,利用傅里叶高斯变换推导出部分相干高斯-谢尔(GSM)光束在大气湍流中的强度分布表达式,并在此基础上分析了大气湍流对光束展宽、以及光束漂移的影响。数值模拟表明:光束展宽和光束漂移与光束的初始半径、波长、光源的相干宽度以及发射机的位置高度有关,并提出了减小湍流影响的措施。

Based on the extended Huygens-Fresnel integral, the cross-spectral density and Rytov＇s phase structure function, average intensity was derived by a formula for the Fourier transform of Gaussian function. Then mean squared root beam width, beam wander of a partially coherent Gaussian-Schell-model （GSM） beam in turbulent atmosphere were found out. It shows that beam spread and beam wander have relation with initial beam radius, initial coherence width, wavelength and transmitter hight in the atmospheric turbulence. At last, some measures were brought to decrease the effect of atmospheric turbulence.