Study On Infrared Scattering Characteristics And Scene Simulation Of Ice

Ice has strong directional scattering and strong scattering radiance,which affects the target detection and recognition of the satellite to the ground.The research on ice scattering characteristics and its scene simulation technology has important significance in various fields,especially in the military field.Because of the special scattering characteristics of ice,the calculation methods of the scattered radiation for the general underlying surface cannot be applied to the problem of ice scattering.In addition,in some special fields,it is necessary to obtain scene images in real time,and satellites have flaws in the real-time performance of ice observations.Therefore,it is necessary to perform real-time simulation of ice scenes through simulation technology.The bidirectional reflectance distribution function(BRDF)was used to model and calculate the infrared scattering characteristics of the ice in this thesis,and the remote sensing scene was simulated to generate a simulation image of the scene.The infrared band selected in this thesis was 2.5~3 um,which has smaller background interference and larger contrast between target and background,which makes it easier to detect targets.The main research contents and achievements of this thesis are as follows:(1)The basic scattering process of ice was studied.The modeling method of bidirectional reflectance distribution function was analysed in detail.Through statistical analysis,the remote sensing images of the ice of the Yellow River and the ice of the Qinghai Lake were interpreted using the histogram method,and the respective characteristics of the two types of ice was discussed.(2)A modeling method for calculating the infrared scattering characteristics of ice was proposed.Firstly,a bidirectional reflectance distribution function model of ice was established,and then an infrared scattering model of ice was established according to the different ice characteristic parameters corresponding to different types of ice,then calculate the radiance of the Yellow River ice,sea ice,and lake ice.The calculation method of the scattered radiation brightness when covered with snow was discussed.The calculated radiance value and radiance value measured by remote sensing can reach the same order of magnitude.And the model can better simulate the strong directional scattering characteristics of ice.(3)The sensitivity of the model for ice infrared scattering characteristics established in this thesis was investigated.The sensitivity of the model was studied by the spectral scattering radiation brightness graph and the integrated scattered radiation brightness graph from the ice feature parameters,the solar irradiation geometric parameters,and the altitude.The calculation results in the sensitivity analysis provide important reference data for the inversion work related to ice.(4)The simulation method of infrared remote sensing scene of ice was proposed,the simulation image of the Yellow River ice and Qinghai Lake ice was generated,and the influence of the sun zenith angle,the zenith angle and the relative azimuth angle on the scene simulation image was discussed.(5)Ice infrared scattering characteristics calculation and scene simulation software was developed.Ice infrared scattering characteristics can be calculated according to the input parameters set by the user and simulate the scene,calculation and simulation results can be displayed on the interface,and results can be saved as files and pictures.