红外系统对战机的探测性能仿真分析

Simulation analysis of detecting capability of infraredsystem for fight plane

通过新建战机尾焰的红外辐射椭圆体模型,改进了战机红外辐射的计算方法,并得到了战机在3~5μm波段红外辐射的空间分布曲线。通过对该曲线的分析,发现该战机的红外辐射在机尾和机头各有4个辐射强度相同的极值方向。考虑到臭氧在3~5μm波段内的吸收、地面遮挡红外辐射传输和探测大气层外目标等因素,引入红外辐射大气传输距离概念进一步完善3~5μm波段红外辐射大气传输模型。以归一化探测度不同的2种红外探测器构建的红外系统为例,仿真得到战机的作用距离随探测方向变化的曲线。计算结果表明,红外系统对战机的作用距离极值并不在战机红外辐射极值方向上,且当系统作用距离较远时,大气衰减对作用距离的影响将超过战机红外辐射的影响。

After establishing the infrared radiation ellipsoid modal of plume,the way for calculating IR(infrared radiation)of the fight plane was improved and the space distribution curve of IR in the 3~5μm band of a certain type of fight plane was obtained.The curve showed that there were four directions which had the same maximum IR at the plane nose and the plane rear.Considering the IR absorption of O 3 in the 3~5μm band,the IR transmitting obstruction by the ground and the detecting object in outer atmosphere.The IR atmosphere transmitted model in the 3~5μm band was further improved with the concept of the IR transmission distance in the atmosphere.Taking the infrared system constructed by two kinds of infrared detectors with different normalized detection degrees as an example,the curve of the operating distance to fight plane varying with the detection direction was simulated.The calculation results show that the extreme value of the operating distance for the infrared system to the fight plane is not in the direction of the extreme value for the IR of the fight plane,and when the operating distance of the system is long,the influence of atmospheric attenuation on the operating distance will exceed the influence of the IR of the fight plane.