临近空间高速运动目标的紫外散射辐射光谱特性研究

With the urgent need for target detection and early warning of high speed target in near space, this project aims to study the physical interaction relationship with high speed target and electromagnetic waves. Based on the temperature model of shock layer，the theory of light scattering and radiation, and the theory of radiative transfer we want to find new optical methods and new theories in the field of detection and recognition a target in the near space environment. In this project, we want to study the following questions. Based on the scattering and radiation BRDF spectrum modeling of some typical sample, the composite model of target in UV band will be establish. Based on the plume flow field data in the reference, the main parameters such as the temperature field could be obtained. Combined with the feature of band absorption and scattering phase function, ultraviolet plume radiative transfer model could be established. Both surrounding particles in the atmosphere in the near space and other ultraviolet radiation characteristics of environment will be considered. And the relationship with the shock layer models between velocity and the ultraviolet radiation characteristics will be constructed. Researches about up ward path for space-based observation's ultraviolet radiation and scattering transmission characteristics model will be establish for high speed target detection and early warning in near space. Combining with the physical properties of the near space atmosphere, calculations of high speed target and shock layer of ultraviolet radiation will be analyzed. And the signal-to-noise ratio of the UV radiation with background will be calculated. This kind of researches will provide the basis for the selection of better detection wavelength or azimuth position in the UV band. The effect on strong coupling, nonlinear effect will be explored in the above researches. If this application will be approved, more researches will be deliberated for space-based observation of high speed moving target. And this kind of researches will provide theory basis for early warning, detection and identification of high speed target in near space in the UV band and at the same time it could provide theory basis for us to develop high speed target in near space for ourselives.

针对高速运动目标探测预警的迫切需求，本项目拟基于高速运动目标气动加热产生的激波层温度场分布，利用光的散射及辐射理论，建立目标的紫外光谱散射辐射模型；结合临近空间的物理环境特性，利用辐射输运理论，研究紫外羽烟的辐射传输特性；围绕激波层特征及空气组分特征与高速飞行目标运动特征之间的相关性，进行高运动速度与紫外辐射光谱特性之间的相关性分析；建立针对天基探测的临近空间中高速运动目标的紫外光谱散射辐射亮度的复合模型，结合临近空间环境背景的紫外辐射散射特性，为最佳探测波段、方位的选取提供理论依据。探索强耦合、非线性对高速运动目标紫外辐射亮度的影响。以上研究将对针对天基观测的临近空间中高速运动目标的预警探测与识别提供理论依据，同时也为我国临近空间飞行器的研发、设计等相关研究提供技术支撑。

本项目基于高速运动目标气动加热产生的激波层流场特性，利用光的散射及辐射理论，建立了目标周围绕流场在不同的运动状态下的紫外光谱散射辐射模型。讨论了尾焰中氧化铝粒子的散射特性对辐射传输的影响。围绕激波层的温度密度压强及粒子种类特征探索了典型分子的紫外光谱辐射特性与高速运动目标的运动特征之间的相关性。建立了改进的碰撞-辐射模型，分析了影响典型的分子紫外光谱辐射的影响因素。结合临近空间的大气物理的环境特性，基于辐射输运理论，利用离散球谐坐标方法，研究了紫外羽烟的辐射传输特性。建立了针对天基探测的临近空间中高速运动目标的紫外光谱散射辐射亮度的复合模型，这些问题的研究对分析临近空间中高超声速目标的最佳探测波段的选取、高速运动目标的预警、探测等相关研究提供了理论参考和依据。