GF-5卫星多角度偏振成像仪在轨偏振定标
|
摘要
2018年5月,我国成功发射了高分5号卫星,其上搭载了多角度偏振成像仪。卫星载荷受发射时的振动、在轨空间环境变化以及元器件电路系统老化等因素的影响,各种辐射特性发生变化,从而导致整个载荷辐射性能与在轨前的实验室定标结果之间存在一定偏差。基于海洋耀光对高分5号卫星多角度偏振成像仪的偏振测量定标的方法,并利用在轨测试期间数据,对载荷进行了初步的偏振辐射定标测试。测试结果表明,3个偏振波段(490, 670, 865 nm)线偏振度测量值与理论值有很好的一致性,平均偏差分别约为-0.03、-0.04、-0.01,载荷发射前后偏振测量状态未发生明显改变。基于自然目标的在轨替代定标方法,还可用于多角度偏振成像仪偏振辐射性能随时间变化情况的长期监测。
The Chinese GF-5 satellite was launched successfully in May 2018, which was equipped with a directional polarization camera(DPC). The DPC sensor's radiometric characterization may be affected by many factors, such as the vibration during launch, the outgassing when instrument leaves atmosphere, the ageing of the optics and circuit system, resulting in a certain deviation between the in-flight performance and the preflight radiometric calibration.Based on the in-flight calibration method for polarization measurements of DPC, using the sunlight reflected within the sun's glitter over ocean, the DPC measurements were adopted during its commissioning phase. The preliminary result shows that the measured degree of linear polarization values are consistent with the theoretically values, with small average deviations of-0.03,-0.04,-0.01 for 490, 670, 865 nm bands, respectively. It indicates that the DPC's polarimetric characterization have not been changed significantly after launch. This method is based on natural target,and it can be used to monitor the temporal polarimetric sensitivity of DPC.
The Chinese GF-5 satellite was launched successfully in May 2018, which was equipped with a directional polarization camera(DPC). The DPC sensor's radiometric characterization may be affected by many factors, such as the vibration during launch, the outgassing when instrument leaves atmosphere, the ageing of the optics and circuit system, resulting in a certain deviation between the in-flight performance and the preflight radiometric calibration.Based on the in-flight calibration method for polarization measurements of DPC, using the sunlight reflected within the sun's glitter over ocean, the DPC measurements were adopted during its commissioning phase. The preliminary result shows that the measured degree of linear polarization values are consistent with the theoretically values, with small average deviations of-0.03,-0.04,-0.01 for 490, 670, 865 nm bands, respectively. It indicates that the DPC's polarimetric characterization have not been changed significantly after launch. This method is based on natural target,and it can be used to monitor the temporal polarimetric sensitivity of DPC.
引文
[1] Mishchenko M I, Travis L D. Satellite retrieval of aerosol properties over the ocean using polarization as well as intensity of reflected sunlight[J]. Journal of Geophysical Research,1997,102(16):98917013.
[2] Waquet F, Cairns B, Knobelspiesse K, et al. Polarimetric remote sensing of aerosols over land[J]. Journal of Geophysical Research:Atmospheres, 2009, 114:D01206.
[3] Li Z Q, Hou W Z, Hong J, et al. Directional Polarimetric Camera(DPC):Monitoring aerosol spectral optical properties over land from satellite observation[J]. Journal of Quantitative Spectroscopy and Radiative Transfer,2018, 218:21-37.
[4] Hagolle O, Goloub P, Deschamps P Y, et al. Results of POLDER in-flight calibration[J]. IEEE Transactions on Geoscience and Remote Sensing, 1999, 37:15501566.
[5] Fougnie B, Bracco G, Lafrance B, et al. PARASOL in-flight calibration and performance[J]. Applied Optics,2007, 46(22):5435-5451.
[6] Fougnie B. Improvement of the PARASOL radiometric in-flight calibration based on synergy between various methods using natural targets[J].IEEE Transactions on Geoscience and Remote Sensing, 2016, 54(4):2140-2152.
[7] Qian Honghu, Ye Qinghao, Meng Binghuan, et al. The polarized radiometric theoretical error of spaceborne directional polarimetric camera[J]. Spectroscopy and Spectral Analysis, 2017, 37(5):1558-1565(in Chinese).钱鸿鹄,叶擎昊,孟炳寰,等.星载多角度偏振成像仪偏振辐射测量的理论误差分析[J].光谱学与光谱分析,2017,37(5):1558-1565.
[8] Cox C, Munk W. Measurement of the roughness of the sea surface from photographs of the sun's glitter[J].Journal of the Optical Society of America, 1954, 44:838-850.
[9] Toubbe B, Bailleul T, Deuze J L, et al. In-flight calibration of the POLDER polarized channels using the sun's glitter[J]. IEEE Transactions on Geoscience and Remote Sensing, 1999, 37(1):513-524.
[2] Waquet F, Cairns B, Knobelspiesse K, et al. Polarimetric remote sensing of aerosols over land[J]. Journal of Geophysical Research:Atmospheres, 2009, 114:D01206.
[3] Li Z Q, Hou W Z, Hong J, et al. Directional Polarimetric Camera(DPC):Monitoring aerosol spectral optical properties over land from satellite observation[J]. Journal of Quantitative Spectroscopy and Radiative Transfer,2018, 218:21-37.
[4] Hagolle O, Goloub P, Deschamps P Y, et al. Results of POLDER in-flight calibration[J]. IEEE Transactions on Geoscience and Remote Sensing, 1999, 37:15501566.
[5] Fougnie B, Bracco G, Lafrance B, et al. PARASOL in-flight calibration and performance[J]. Applied Optics,2007, 46(22):5435-5451.
[6] Fougnie B. Improvement of the PARASOL radiometric in-flight calibration based on synergy between various methods using natural targets[J].IEEE Transactions on Geoscience and Remote Sensing, 2016, 54(4):2140-2152.
[7] Qian Honghu, Ye Qinghao, Meng Binghuan, et al. The polarized radiometric theoretical error of spaceborne directional polarimetric camera[J]. Spectroscopy and Spectral Analysis, 2017, 37(5):1558-1565(in Chinese).钱鸿鹄,叶擎昊,孟炳寰,等.星载多角度偏振成像仪偏振辐射测量的理论误差分析[J].光谱学与光谱分析,2017,37(5):1558-1565.
[8] Cox C, Munk W. Measurement of the roughness of the sea surface from photographs of the sun's glitter[J].Journal of the Optical Society of America, 1954, 44:838-850.
[9] Toubbe B, Bailleul T, Deuze J L, et al. In-flight calibration of the POLDER polarized channels using the sun's glitter[J]. IEEE Transactions on Geoscience and Remote Sensing, 1999, 37(1):513-524.