摘要
基于周期性阵列角锥结构星载微波辐射热定标源,运用时域有限差分算法(Finite Difference Time Domain,FDTD),建立有限大辐射体电磁波散射模型,探索该结构下热定标源在6.3～230 GHz内辐射特性变化趋势,分析热定标源辐射性能(包括反射率r和发射率e)随涂层厚度t、角锥高宽比以及角锥宽度p的变化规律。研究结果表明:热定标源反射率在低频段主要依赖涂层吸波性能,高频段则主要取决于涂层界面反射率;在低频段内,随涂层厚度的增加,热定标源反射率逐渐减小,发射率有所增大,但在高频处,呈现出较快的震荡趋势;在特定涂层厚度下,随着角锥高宽比增加,热定标源在全工作频段内反射率减小,发射率增大,且随着角锥宽度的增加,反射率增大,发射率减小。综合热定标源辐射性能研究结果,结合型号产品具体应用需求,设计开发出热定标源产品,并进行发射率测量,实测发射率均为0.998。
FDTD(Finite Difference Time Domain)is used to establish the scattering model of the finite radiator based on the spaceborne microwave radiation thermal calibration source with periodic array of pyramidal structures,and the reflectivity(or emissivity)of the heat calibration source in the structure is investigated between 6.3-230 GHz.And the law of the emissivity of the thermal calibration source changing with the coating thickness,the angle of the pyramid and the aspect ratio of the pyramid are analyzed.The results show that the emissivity of the thermal calibration source in the low frequency range depends mainly on the absorbing performance of the coating,and in high frequency band mainly depends on the reflectivity of the coating.In the low frequency range,as the thickness of the coating increases,the reflectivity of the thermal calibration source gradually decreases,and the emissivity increases,but at high frequencies,it exhibits a faster oscillating tendency;As the aspect ratio of the pyramid increases,the reflectivity of the thermal calibration source decreases in the full operating frequency band,the emissivity increases,and as the pyramid width increases,the reflectance increases and the emissivity decreases at a specific coating thickness.Based on the research results of thermal calibration source emissity,combined with the specific application requirements,the thermal calibration source is developed.The measured emissivity shows 0.998.
作者
陶院
高青松
段福伟
丁成斌
金铭
TAO Yuan;GAO Qing-song;DUAN Fu-wei;DING Cheng-bin;JING Ming(Science and Technology on Vacuum Technology and Physics Laboratory,Lanzhou Institute of Space,Lanzhou 730000,China;Key Laboratory of Microwave Remote Sensing Technology,Chinese Academy of Sciences,Beijing 100094,China)
出处
《微波学报》
CSCD
北大核心
2019年第2期69-74,86,共7页
Journal of Microwaves
关键词
周期性
角锥
微波
热定标源
发射率
periodic
pyramid
microwave
thermal calibration source
emissivity
