飞行器尾焰红外辐射及其被动测距

Infrared radiations of aerocraft exhaust plume and its passive ranging

旨在研究利用飞行器的尾焰辐射对飞行器进行被动测距。导弹和飞机发动机的排气系统是飞机在波段的主要红外辐射源。建模计算了矩形喷管尾焰红外辐射特性,计算结果表明，不管观察方向如何，尾焰红外辐射强度色比是相同的。当辐射强度色比在大气中传输时，因为吸收和散射而被衰减，不同波长上红外辐射衰减幅度不同,辐射强度色比随着传输距离的改变而发生变化，色比包含了目标的距离信息。推导了目标尾焰色比与尾焰温度、辐射传输距离、大气消光系数之间的关系。计算了尾焰色比与尾焰温度的关系，推导出了红外三色比距离方程组，选取4.5、4.6、4.7 三个波长对三色被动测距进行了研究。利用测距方程组画出了测距图。结果表明，利用该方法可对尾焰进行三色测距。

Passive ranging an aerocraft using its exhaust plume infrared radiation was studied. Exhaustsystem of an aircraft or a missile is the main infrared radiant point in 3-5 ｜xm wave-band. The infraredradiant characteristic of rectangular nozzle flame was calculated by modeling. The result shows that theinfrared radiation intensity color ratio of an exhaust plume is same in different direction. When theinfrared radiation transmitted in the atmosphere, it would be attenuated by the absorption and dispersionof the atmosphere. The attenuation was different according to different wavelength. The radiation intensitycolor ratio of different wavelength would change along with the change of transmission distance. Theradiation intensity color ratio contains distance information. The relationship among the color ratio ofexhaust plume and its temperature, its transmission distance, and atmosphere attenuation coefficient werededuced. The relationship between color ratio of an exhaust plume and its temperature was calculated.rared three color ratio ranging equations were deduced. The three wavelength of 4.5, 4.6,4.7 mm wasused to study passive ranging method. A ranging figure was drawn using the equations. The result showsthat the method can be used to range an exhaust plume.