Typical natural backgrounds include land, sea, desert, sky and so on, and experimental measurement is an effective means to obtain background radiation data. Because the background infrared radiation is affected by season, weather and the angle of solar radiation, it is necessary to collect environmental parameters at the same time during testing. The screening and collection of major environmental parameters is crucial for subsequent radiation data processing. In view of this problem, first of all, the influence of environmental reference on background infrared radiation was theoretically calculated by MODTRAN software, and the main parameters were screened out. A test program for radiation measurement of natural background is formed, which is used as a reference for the design of background infrared radiation measurement.
Cloud is an important natural phenomenon, and its radiation causes serious interference to infrared detector. Based on fractal and statistical data, a method is proposed to realize cloud background simulation, and cloud infrared radiation data field is assigned using satellite radiation data of cloud. A cloud infrared radiation simulation model is established using matlab, and it can generate cloud background infrared images for different cloud types (low cloud, middle cloud, and high cloud) in different months, bands and sensor zenith angles.