地物微波辐射亮温的图像模拟方法

Image Simulation for Ground Objects Microwave Radiation

微波辐射亮温图像的模拟在被动遥感领域中具有重要意义。该文根据射线追踪的思想提出了一种三维场景微波辐射图像的模拟方法:亮温追踪法。分析了模拟时必须考虑的天空背景辐射、多次反射造成的极化旋转以及天线平滑作用等影响因素,最终建立了微波辐射亮温图像的模拟方法。应用此方法对典型目标进行了试验模拟,并对模拟结果所表现出的微波辐射现象进行了分析。为验证模拟方法的可靠性,该文对楼层建筑以及飞机跑道等实际场景进行模拟,模拟结果与实地测量图像取得了很好的一致,表明此方法完全可行。

The simulation of brightness temperature image is a necessary work in the passive microwave remote sensing. This paper introduces the brightness temperature tracing method for 3-D scene microwave radiometric image simulation, and describes the general requirements and considerations such as sky radiation, antenna smoothing and polarization rotation caused by multiple-reflection. Then a simulation model is established which can create more realistic imagery and reproduce the radiation phenomenology. Using this model the microwave radiometric phenomenology which is greatly deferent from optical and infrared ones is analyzed. Finally, the Lab building and airstrip are simulated in order to validate this model. The comparisons with field measurements indicate that this model is completely feasible in practice.