| Targets and environment characteristics are of important research value not only in the military field, but also in civilian areas such as remote sensing. Providing simulation data for kinds of equipment, targets and environment can be used for target detection and recognition by calculating and image processing, according to different characters of targets and environment. In civilian areas, especially in the remote sensing, target environment is also potential for a wide range of application. It can monitor environment changes effectively and improve search and rescue capabilities when natural disasters happen, thus unnecessary losses can be reduced. The main contents of this paper are as follows:1. MODIS satellite data is used as the surface environment. In order to obtain surface upward radiance, a variety of MODIS satellite data is applied. The MODIS1 B radiance data and MODIS43 BRDF data are used in the visible band. MODIS1 B is radiance data containing directionality, which is the radiance received by satellites from the sun. This paper shows the relationship between the radiance of different directions and the radiance of specific direction, and the radiance of different directions are caculated, which can be regard as one of the factors that affecting target radiation characteristics.2. With the parameters of sea surface salinity, wind speed, and temperature from Aquarius satellite data, the sea surface infrared radiation characteristics are inverted. For far area waters, it is very difficult to experimentally obtain the characteristics of the sea, but with the use of satellite data, the problem can be easily solved. The paper simulates the sea surface undulating spectrum combining wind speed from satellite data with PN spectrum. The sea surface temperature is used to calculate radiance. With the sea surface BRDF, the radiance of any angle can be obtained.3. A simple algorithm for the calculation of target scattered radiation brightness in the visible range is given in this paper. The algorithm converts the integral of angle to the integral of the area, thus, the computational efficiency is improved, but the accuracy is still in discussion. With this method, the scattering radiance of the target is calculated and imaged, and the target radiation characteristics of each part can be observed intuitively, which makes it easy to detect targets.4. With the FLUENT software, the aerodynamic heating temperature field of the target is calculated. Friction of the high-speed flight target and atmosphere produces a lot of heat. The calculation of infrared radiation should take the impacts of target skin temperature on the infrared radiation into consideration. The temperature fields of flying targets at different speeds are calculated in this paper and the infrared radiation images are obtained. SE software is used to calculate the temperature fields of high-speed flying targets considering the impact of plume.The sea surface is modeled in this article, giving their radiation and scattering properties, which can reflect the characteristics of the sea at different times and locations. A simple method to calculate the target radiation and scattering properties in visible light band and infrared band is presented, taking the aerodynamic heating and the plume of radiation characteristics of the target into account, which can be used in target detection and identification. Under the circumstances of the high experiment cost and requiring a lot of work, this paper provides a method for calculating the high-speed flying targets radiance, and offers theoretical support for target detection and identification. |
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