红外与激光工程
紅外與激光工程
홍외여격광공정
INFRARED AND LASER ENGINEERING
2015年
4期
1301-1305
,共5页
大气光学%大气闪烁%功率谱
大氣光學%大氣閃爍%功率譜
대기광학%대기섬삭%공솔보
atmospheric optics%atmospheric scintillation%power spectrum
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150 Hz。
為瞭深入認識大氣閃爍的時間頻域特性,給在大氣中工作的光學繫統的工程設計和性能評估提供參攷,理論推導瞭大氣閃爍功率譜的通用解析錶達式,數值研究瞭不同傳輸條件下大氣閃爍的時間頻域特性。孔徑接收下,對于水平均勻路徑,平麵波閃爍功率譜高頻區近似呈現-17/3冪率,毬麵波近似呈現-11/3冪率;對于整層下行路徑,高頻區均近似呈現-17/3冪率,低頻區與高頻區之間存在一緩變區,孔徑越大,緩變區越寬。典型大氣條件下低頻區加上緩變區的頻譜寬度約為150 Hz。
위료심입인식대기섬삭적시간빈역특성,급재대기중공작적광학계통적공정설계화성능평고제공삼고,이론추도료대기섬삭공솔보적통용해석표체식,수치연구료불동전수조건하대기섬삭적시간빈역특성。공경접수하,대우수평균균로경,평면파섬삭공솔보고빈구근사정현-17/3멱솔,구면파근사정현-11/3멱솔;대우정층하행로경,고빈구균근사정현-17/3멱솔,저빈구여고빈구지간존재일완변구,공경월대,완변구월관。전형대기조건하저빈구가상완변구적빈보관도약위150 Hz。
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 obey the power law with an exponent of -17/3 in the high frequency area, and there is a slow transformation area between the low frequency area and the high frequency area. The larger the aperture becomes, the wider the slow transformation area grows; besides the frequency spectrum width of the low frequency area and the slow transformation area is about 150 Hz under typical atmosphere conditions for plane wave .