湍流大气中斜程相干长度的修正

Revision to coherence length of slant path in atmospheric turbulence

基于大气传输模型,采用光线传输的实际轨迹对天顶角进行修正处理,得出天顶角随发射角和传输高度的变化复杂函数.并通过仿真分析得到,天顶角与发射角间的偏差随发射角的增大是先增加后减小,在π/4时偏差达到最大;随高度的增加而增大,但到达某一高度时将趋于饱和.相干长度的偏差趋势与天顶角偏差相似.修正后的相干长度总比传统相干长度偏小,因为修正后的天顶角比发射角大.图6,参7.

Based on the atmospheric transmission model, through the actual ray track, the zenith angle is revised, which is a complicated function with launch angle and altitude. And the results of simulation show that the dispersion between zenith angle and launch angle,first increase then decrease, varies with launch angle, and gets to maximum when launch angle is π/4 The dispersion also increases with altitude. To a great extent, the dispersion of coherence length is the same as zenith angle. The coherence length revised is smaller than the classical, because the revised zenith angle is larger than the launch angle.