摘要
考虑到光束通过大气时受到大气湍流的影响,理论上分析了到达角起伏的原因,通过利用马尔科夫和平均强度的平方近似所求得到达角起伏公式,采用变形谱 Von Karman 所得出的波结构函数 D(ρ,z),得出到达角起伏在考虑湍流内外尺度和强度影响下的到达角方差表达式.并在垂程方向上分析得出到达角方差随 L 增大而增大,在小于250 m 范围内,仅考虑湍流强度与考虑了湍流尺度和强度的影响相比,两者较接近,大于250 m 以后,考虑了湍流尺度和强度的影响比仅考虑湍流强度影响的大.
Considering the influence of the atmospheric turbulence when a beam of light goes through the atmosphere,the reason of angle of arrival (AOA) fluctuation is analyzed.By use of the formula of angle of arrival (AOA) fluctuation under the suppositions of Markov random process and the approximate square of average intensity,and the wave structure function that uses Von Karman-spectrum,a universal formula of angle of arrival fluctuation variance σ_α~2 under the effects of turbulent scale and intensity is got.Then at the vertical way,the conclusions are drawn that angle of arrival fluctuation variance σ_α~2 augments with the augmentation of the distance (L),and over 250 meters,the result of angle of arrival fluctuation variance 0-2 which considers of the effect of turbulent scale and intensity is greater than that of only considering turbulent intensity,but they are almost below 250 meters.
出处
《红外与激光工程》
EI
CSCD
北大核心
2006年第z1期437-441,共5页
Infrared and Laser Engineering
基金
国家自然科学资金(60572079)
