一种精确快速的大气吸收工程计算模型

逐线积分法计算大气吸收透过率虽然具有最高的计算精度,但实时性欠佳,限制了其工程应用价值。针对红外实时仿真的工程应用背景,提出了一种光谱分辨率为1 cm-1的大气吸收计算模型,能够兼顾计算精度和实时性要求。利用逐线积分计算得到恒定气压、温度、分子浓度和不同传输距离条件下,气体分子1 cm-1波段吸收透过率并建立了吸收透过率与高度的数学模型,进而插值计算任意路径下气体的吸收。实验表明,大气吸收透过率的计算精度高于MODTRAN,并且运算速度远快于逐线积分法。

Accurate and fast engineering calculation model of atmosphere transmittance

The model of line-by-line integration has the greatest accuracy in atmosphere absorption transmittance calculation,but its poor realtime property limits its application in engineering. A model of atmosphere absorption transmittance with spectral resolution of 1 cm-1 is given for IR scene real-time engineering simulation,and it can meet the demands of realtime and accuracy. Firstly,the gas transmittance of 1 cm-1 band with constant temperature,pressure,gas density and different distance is calculated by line-by-line integration,and the models of absorption transmittance and altitude are built. The gas absorption transmittance on random route is calculated by interpolation finally. The results show that the accuracy of the atmosphere absorption transmittance calculated by the model is better than that of MODTRAN,and the calculation speed of the model is much faster than that of line-by-line integration.