大气闪烁的时间频域特性的研究.pdfVIP

第44卷第4期 红外与激光工程 2015年4 月 Vol.44No.4 InfraredandLaserEngineering Apr.2015 大气闪烁的时间频域特性研究 沈 红，范承玉，于龙昆 (中国科学院安徽光学精密机械研究所 中国科学院大气成分与光学重点实验室，安徽 合肥 230031) 摘 要院为了深入认识大气闪烁的时间频域特性，给在大气中工作的光学系统的工程设计和性能评 估提供参考，理论推导了大气闪烁功率谱的通用解析表达式，数值研究了不同传输条件下大气闪烁的 时间频域特性。孔径接收下，对于水平均匀路径，平面波闪烁功率谱高频区近似呈现-17/3幂率，球面 波近似呈现-11/3幂率；对于整层下行路径，高频区均近似呈现-17/3幂率，低频区与高频区之间存在 一缓变区，孔径越大，缓变区越宽。典型大气条件下低频区加上缓变区的频谱宽度约为150Hz。 关键词院大气光学； 大气闪烁； 功率谱 中图分类号院TN929.1 文献标志码院A 文章编号院1007-2276(2015)04-1301-05 Characteristics of the temporal spectrum of atmospheric scintillation Shen Hong, Fan Chengyu, Yu Longkun (Key Laboratory of Atmospheric Composition and Optical Radiation, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031 China) Abstract: In order to thoroughly understand the characteristics of the temporal spectrum of atmospheric scintillation and provide references for engineering design and performance evaluation of the optics system employed in the atmosphere, the generally analytic expression of the atmosphere scintillation power spectrum was theoretically deduced and the frequency domain characteristics of atmospheric scintillation under different propagation conditions was numerically investigated. For horizontal path with an aperture receiver, in the high frequency area, the scintillation power spectrum of the plane wave obeys the power law with an exponent of -17/3, while the scintillation power spectrum of the spherical wave obeys the power law with an exponent of -11/3; for the whole layer downlink path, the scintillation power spectra