Temporal spectrum of atmospheric scintillation and the effects of aperture averaging and time averaging

The general analytic expression for the temporal spectrum of atmospheric scintillation under weak turbulence condition is derived. It was employed to study the characteristics of the temporal spectra for horizontal uniform path and whole layer atmospheric non-uniform path. In the non-uniform path, the H-V turbulence model and the Gaussian wind speed model are utilized. It has been found that when the receiver diameter is larger than Fresnel scale (λL)1/2, the temporal spectrum of the plane wave have a power law behavior with a scaling index – 17/3 in high-frequency range. The change of the turbulence strength has little influence on the shape of the temporal spectrum. Based on the characteristics of the temporal spectrum, the aperture-averaging and time-averaging effects on scintillation were analyzed in the frequency domain.

[1]  M Toyoshima,et al.  Effects of time averaging on optical scintillation in a ground-to-satellite atmospheric propagation. , 2000, Applied optics.

[2]  Christopher C. Davis,et al.  Aperture averaging for optimizing receiver design and system performance on free-space optical communication links , 2005 .

[3]  J. Churnside.  Aperture averaging of optical scintillations in the turbulent atmosphere. , 1991, Applied optics.

[4]  Steven F. Clifford,et al.  Temporal-Frequency Spectra for a Spherical Wave Propagating through Atmospheric Turbulence , 1971 .

[5]  Yoshihisa Takayama,et al.  Atmospheric turbulence-induced fading channel model for space-to-ground laser communications links. , 2011, Optics express.

[6]  S. Bourennane,et al.  Fading Reduction by Aperture Averaging and Spatial Diversity in Optical Wireless Systems , 2009, IEEE/OSA Journal of Optical Communications and Networking.

[7]  Norman S. Kopeika,et al.  Some limitations on optical communication reliability through Kolmogorov and non-Kolmogorov turbulence , 2010 .

[8]  David L. Fried,et al.  Aperture Averaging of Scintillation , 1967 .

[9]  L. Andrews,et al.  Aperture averaging effects on the probability density of irradiance fluctuations in moderate-to-strong turbulence. , 2007, Applied optics.

[10]  David A Kozlowski,et al.  Low Earth orbit satellite-to-ground optical scintillation: comparison of experimental observations and theoretical predictions. , 2011, Optics letters.

[11]  Katsutoshi Tsukamoto,et al.  Spectral model of optical scintillation for terrestrial free-space optical communication link design , 2011 .