微波辐射计天线热控涂层表面反射率研究
|
摘要
静止轨道微波辐射计天线反射面外热流变化剧烈,反射面表面存在较大温度梯度,为满足在轨热变形要求,反射面采用高强度、低膨胀系数的碳纤维复合材料,采用磁控溅射工艺在碳纤维表面真空沉积铝和二氧化硅,获取满足热控要求的吸收发射比。由于二氧化硅是损耗材质,本文根据相干反射理论分析二氧化硅层对天线表面反射率的影响,采用辐射计噪声温度法对热控涂层试片反射率进行测试,反射率理论分析和测试值一致。
External heat flux changes violently of the reflector of the stationary orbit microwave radiometer. There is a large temperature gradient on the surface of the reflector. To reduce the thermal deformation of the antenna on orbit, high strength and low expansion coefficient carbon fiber composites are used in the reflector. And it is a vacuum deposition of layer of aluminum and silica on the surface of carbon fibers by magnetron sputtering, obtaining the absorption and emission ratio to satisfy the thermal control requirements. Because the silica is a lossy material, it will produce ohmic loss on the receiving power of the antenna, absorbed by antenna in the form of heat loss. Therefore, it is necessary to analyze the surface reflectivity of the thermal control coating. Based on coherent reflection theory, the influence of silica layer on reflectivity of antenna is analyzed in this paper. Radiometric noise temperature method is used to test the reflectivity of coated specimen. The reflectivity theoretical analysis and test values meet requirements for electrical performance of antennas. It can optimize the test platform to improve the accuracy of reflectivity test.
External heat flux changes violently of the reflector of the stationary orbit microwave radiometer. There is a large temperature gradient on the surface of the reflector. To reduce the thermal deformation of the antenna on orbit, high strength and low expansion coefficient carbon fiber composites are used in the reflector. And it is a vacuum deposition of layer of aluminum and silica on the surface of carbon fibers by magnetron sputtering, obtaining the absorption and emission ratio to satisfy the thermal control requirements. Because the silica is a lossy material, it will produce ohmic loss on the receiving power of the antenna, absorbed by antenna in the form of heat loss. Therefore, it is necessary to analyze the surface reflectivity of the thermal control coating. Based on coherent reflection theory, the influence of silica layer on reflectivity of antenna is analyzed in this paper. Radiometric noise temperature method is used to test the reflectivity of coated specimen. The reflectivity theoretical analysis and test values meet requirements for electrical performance of antennas. It can optimize the test platform to improve the accuracy of reflectivity test.
引文
[1]Gasiewski A J,Voronovich A.Geosynchronous Microwave(GEM)Sounder/Imager Observ Simulation[J].IEEE.Trans.2003:1209-1211.
[2]Bizzarri B,et al.Initiatives for Millimetre/Submillimetre-Wave Sounding from Geostationary Orbit[J].Geoscience and Remote Sensing Symposium,vol.1,2002:548-552.
[3]王彦,康奥峰,曹韫真,江世臣.静止轨道实孔径微波天线主反热控方案研究[J].上海航天,2016,33(5):107-113.Wang Yan,Kang aofeng,Cao yunzhen,Jiang shichen.Research of Real Aperture Microwave Antenna Main Reflector Thermal Control Measures on Geostationary Earth Orbit[J],2016(5):107-113.
[4]F.T.乌拉比,R.K.穆尔,冯健超.微波遥感(第一卷).[M].北京:科学出版社,1988,123-166F.T Ulaby,R.K.Moore,A.K.Fung,Microwave remote sensing(Volume 1).Beijing:Science Press,1988,123-166
[5]David B,Steven D,Gene A,Ye Hong,and Michael F.Special Sensor Microwave Imager Sounder(SSMIS)Radiometric Calibration Anomalies-Part I:Identification and Characterization.IEEE Transactions on Geoscience and Remote Sensing,Vol 46,No 4,2008(4):1017-1033
[6]Niels Skou.Measurement of Small Antenna Reflector Losses for Radiometer Calibration Budget.IEEETransactions on Geoscience and Remote Sensing,Vol 35,No 4,1997(7):967-971
[2]Bizzarri B,et al.Initiatives for Millimetre/Submillimetre-Wave Sounding from Geostationary Orbit[J].Geoscience and Remote Sensing Symposium,vol.1,2002:548-552.
[3]王彦,康奥峰,曹韫真,江世臣.静止轨道实孔径微波天线主反热控方案研究[J].上海航天,2016,33(5):107-113.Wang Yan,Kang aofeng,Cao yunzhen,Jiang shichen.Research of Real Aperture Microwave Antenna Main Reflector Thermal Control Measures on Geostationary Earth Orbit[J],2016(5):107-113.
[4]F.T.乌拉比,R.K.穆尔,冯健超.微波遥感(第一卷).[M].北京:科学出版社,1988,123-166F.T Ulaby,R.K.Moore,A.K.Fung,Microwave remote sensing(Volume 1).Beijing:Science Press,1988,123-166
[5]David B,Steven D,Gene A,Ye Hong,and Michael F.Special Sensor Microwave Imager Sounder(SSMIS)Radiometric Calibration Anomalies-Part I:Identification and Characterization.IEEE Transactions on Geoscience and Remote Sensing,Vol 46,No 4,2008(4):1017-1033
[6]Niels Skou.Measurement of Small Antenna Reflector Losses for Radiometer Calibration Budget.IEEETransactions on Geoscience and Remote Sensing,Vol 35,No 4,1997(7):967-971