Effects of the turbulent scales on aperture averaging of a Gaussian-Schell beam propagation in a turbulent atmosphere

ZHANG Yi-xin; TAO Chun-kan

The effects of atmospheric scales on aperture averaging of Gaussian-Schell beam propagating in an atmospheric turbulence were examined by means of a modulation spectrum for the index of refraction fluctuations including the outer-and-inner scales of the atmospheric turbulence and the approx imation of across-spectral density function for the coherent function.An easily evaluated expression valid in the weak fluctuation regime for aperture-averag ing factor including the effects of the turbulent outer-scale was obtained.The results show that with the outer-scale reducing,the aperture averaging of scintillations for Gaussian-Schell beam propagating in an atmospheric turbulence will reduce.The effect of the outer-scale of turbulence on the aperture averaging of scintillations for incoherence beam can be ignored.

Corresponding author: TAO Chun-kan, taock812@sohu.com

1. School of Science, Southern Yangtze University, Wuxi 214036, China;

2. School of Science, Nanjing University of Science and Technology, Nanjing 210014, China

Received Date: 2004-01-04

Accepted Date: 2004-10-12

Available Online: 2005-05-25

Abstract: The effects of atmospheric scales on aperture averaging of Gaussian-Schell beam propagating in an atmospheric turbulence were examined by means of a modulation spectrum for the index of refraction fluctuations including the outer-and-inner scales of the atmospheric turbulence and the approx imation of across-spectral density function for the coherent function.An easily evaluated expression valid in the weak fluctuation regime for aperture-averag ing factor including the effects of the turbulent outer-scale was obtained.The results show that with the outer-scale reducing,the aperture averaging of scintillations for Gaussian-Schell beam propagating in an atmospheric turbulence will reduce.The effect of the outer-scale of turbulence on the aperture averaging of scintillations for incoherence beam can be ignored.

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Reference (14)

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Effects of the turbulent scales on aperture averaging of a Gaussian-Schell beam propagation in a turbulent atmosphere

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通讯作者: 陈斌, bchen63@163.com

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