Infrared remote sensing imaging simulation method for earth’s limb scene

Simulation of earth’s limb scene plays a key role in satellite infrared detection field. It is an important basis for long-range detection of high-speed airborne targets. In limb detection, the traditional infrared ocean simulation method based on three-dimensional ocean appearance and the calculation of radiation characteristics is not applicable, because the earth surface approximates a sphere. Also, the thickness and height of clouds have important influence on the calculation of infrared radiative transmission characteristics, where the method of considering the cloud as particle cluster would greatly reduce the speed of simulation. Therefore, the infrared remote sensing imaging simulation method for earth’s limb scene was established by conducting the infrared radiation model of ocean and cloud, the transformation relationship between earth-space coordinate system and infrared camera coordinate system, and the atmospheric transmission model. According to the components of scene, the ocean distribution model and multi-layer clouds distribution model were established respectively, and the infrared radiation model of the earth’s limb scene was established according to the infrared radiation and reflection characteristics of ocean and clouds. The infrared remote sensing simulation images of the earth’s limb scene under various observation angles were calculated by the conversion relationship between earth-space coordinate system and camera coordinate system, the theory of atmospheric transmission and the sensor effect. The simulation results show that the infrared image accord with the infrared radiation characteristics of earth’s limb scene. The average Laplacian sum of simulation images is 0.15, and the grayscale gradient average value of the images is 0.70.