Calculation Of The Operating Range Of Infrared System Under Complex Atmosphere Condition Based On The MODTRAN

In recent years, due to the infrared imaging system capable of working at night and in badweather conditions, faraway operating distance and passive work, can not be easily found andinterference, has been attention by the world and widely used in military and civilian fields ofaerospace detection, remote sensing, night vision, imaging-guided tracking, astronomy, medicalimaging, industrial fault diagnosis. Therefore, the infrared imaging system performanceevaluation is a very important significance of theoretical study and practical application. Theoperating distance is one of the important parameters of infrared imaging system, evaluate it ofgreat significance to improve the level of system design, reduce costs and shorten thedevelopment cycle.The operating distance of infrared imaging system with a number of factors related, mainlyas infrared radiation characteristics of the target, the transmission characteristics of infraredradiation in the atmosphere, and infrared imaging system performance. This paper derived andanalyzed the infrared imaging system distance formula, introduced the operating distanceinfluencing factors of infrared imaging system from three respect as the target and backgroundinfrared radiation characteristics, the absorption、scattering and attenuation of infrared radiationin the atmosphere, and system performance. Atmosphere environmental has a great impact ofinfrared radiation, which is an important factor to affect the infrared imaging system distance,and difficult expression to use exact mathematical formulas, is considered to be a difficulty tocalculate the distance of infrared imaging system.In this paper, the MODTRAN software for the calculation of atmospheric transmittanceinternationally recognized. The MODTRAN software on atmospheric transmittance calculationstake full account of the water vapor, carbon dioxide, carbon monoxide, methane, ozone and othersubstances on the attenuation of the infrared radiation, and atmospheric temperature, humidity,altitude, visibility, observation path, propagation distance and other factors on the influence ofthe transmittance, the calculation result is accurate. By setting atmospheric parameters anddetection parameters of the MODTRAN software can get the required atmospheric transmittancedata，then run the MODTRAN software to create different atmospheric conditions, at differentelevations, different path atmospheric transmittance database. Cruise missile has the penetrationability, high accuracy, and flexibility advantages of much national military attention, in recentyears has developed into important airstrike weapon of modern warfare. Therefore effectiveagainst cruise missiles is an important issue of air defense operations. Correctly estimate theinfrared imaging system operating distance of the cruise missiles is the basis for detection of early warning and effective fight against. Take the thermal imager of Catherine-GP model forexample, the operating distance of this thermal imager acting on Tomahawk cruise missiles hasbeen calculated according to the data of the operating distance formula and atmospherictransmittance from this article. The results show that the method is feasible.Finally, using MATLAB software to calculate the target infrared radiation and atmospherictransmittance database is called to calculate the distance of infrared imaging system. Accordingto the model, write a real-time calculation of the distance of infrared imaging system software.