大气湍流对遥感系统分辨力的影响

以平面波为例,分别针对较弱和较强的湍流模型,通过计算到达角起伏讨论了高空光学遥感系统由大气湍流引起的地面图像分辨力问题。结果表明,对于给定的遥感系统口径和高度,较强湍流引起的图像分辨力的1cm左右;而较强湍流引起的图像分辨力则可达10cm量级。对于自身的地面分辨力具有m的量级的传统光学遥感系统,上述影响并不明显。对于现代高辨力光学遥感系统,这种影响便不容忽略,特别是对较强的湍流,往往需要用自适应光学等方法加以补偿。

Effect of the turbulence on the image resolution of the remote sensing system

That the image resolution of an optical remote system caused by the weaker and stronger turbulence, respectively by computing the fluctuation of angle of arrival for plane wave are presented. The result shows that the resolution caused by the weaker turbulence is about 1cm while it may reach 10cm for stronger turbulence for given pupil size and altitude of the image system. Aforementioned effects are not evident for conventional remote sensing system possessing an image resolution of level meter. It is, however, serious for an advanced optical remote sensing system with the fine resolution and an adaptive optics correct is needed in such cased.