Influence of background radiation on space target detection in the long wave infrared range

Aiming at the space target and two dominant background sources including the sun and earth-atmosphere system, their radiation models are established, and the background influence on the space target detection for the space-based infrared imaging system are discussed in the long wave infrared (8 to 14 mu m) range. From the numerical calculation and analysis, we find that the earth-atmosphere system is the strongest background interference source and will form a big detection blind zone, followed by the sun, whose irradiance is about 1.6% of that from the earth-atmosphere system. Compared with these two intense radiations, the space target radiation acting on the space-based infrared detector is so weak that it may be submerged once the target appears in the earth-atmosphere or solar backgrounds. Thus, in order to reduce the influence of the background interferences, necessary measures must be taken to control the space-based infrared detector and its host platform in real time, such as adjusting the flight attitude, changing the detection angle, transferring operating orbit, and so on. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.OE.51.8.086402]