Data processing of on-orbit spectral calibration of space-borne high resolution imaging spectrometer
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摘要:为了提高仪器光谱定标精度,降低谱线偏移对地物反射光谱数据反演精度的影响(特别是大气吸收峰附近),根据星上光谱定标的特点,介绍了星上光谱定标数据处理的常用方法。通过对实验室光谱定标时两种典型工况的比较,实现了星上定标数据处理算法的地面仿真,验证了算法的可行性,并比较了各自的优缺点。结果表明,基于谱线匹配的标准差法、相关系数法和最小差值法计算精度较高,但计算效率较低;基于多项式拟合的极值法计算精度较低,但是计算效率较其他算法提高1个数量级。用极值法对数据进行预处理,快速确定谱线偏移量,再用谱线匹配算法在小范围内精确计算谱线偏移量,可以在不影响计算精度的前提下提高运算速度,计算精度优于1 nm,满足成像光谱仪星上光谱定标的精度要求。Abstract:In order to improve the spectral calibration precision of a High Resolution Imaging Spectrometer(HRIS) and to reduce the influence of the spectral shift on the surface reflectance retrieving of the ground spectra, especially in those wavelengths mostly affected by gaseous absorptions, the common data processing algorithms used in the on-orbit spectral calibration are introduced. The feasibility of these different algorithms is verified and their advantages and disadvantages are emulated with two cases of the laboratory spectral calibration under a thermal vacuum environment. It is shown that the algorithm based on spectra-matching, such as standard deviation method, correlation coefficient method and the minimized difference method can offer an advantage in the processing precision, and the extreme value method based on polynomial-fitting works much better in the processing speed. If polynomial-fitting method confirms the spectral shift fleetly in the pretreatment phase firstly, the spectral bound for spectral matching processing will be narrowed. A new algorithm with high processing precision and fast processing speed which combines spectra-matching and polynomial-fitting ideas was presented, it can offer the band-center wavelength accuracy better than 1 nm and can meet the need of the on-orbit spectral calibration precision of the HRIS.
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[1] 于斌, 曹召良,禹秉熙. 二元光学透镜在超光谱成像仪中的应用[J]. 光学 精密工程 ,2003,2(11):157-161. YU B,CAO ZH L,YU B X. Application of binary optical lens in hyperspectral imager[J].Opt. Precision Eng.,2003,2(11):157-161.(in Chinese) [2] GREEN R O. Spectral calibration requirement for earth-looking imaging spectrometers in the solar-reflected spectrum[J].Appl. Opt.,1998,37(4):683-690. [3] 李晓晖,颜昌翔. 成像光谱仪星上定标技术[J]. 中国光学与应用光学 ,2009,2(4):309-315. LI X H,YAN CH X. Onboard calibration technologies for hyper-spectral imager[J].Chinese J. Opt. and Appl. Opt.,2009,2(4):309-315.(in Chinese) [4] XIONG X,CHIANG K,ESPOSITO J,et al.. MODIS on-orbit calibration and characterization[J].Metrologia,2003,40:89-92. [5] IMMERMANN G,NEUMANN A,SIIMNICH H,et al.. MOS/PRIROD-an imaging VIS/NIR spectrometer for ocean remote sensing[J].SPIE,1993,1937:201-206. [6] BLECHINGER F,CHARLTON D E,DAVANCENS R,et al.. High resolution imaging spectrometer(HRIS):optics, focal plane and calibration[J].SPIE,1993,1937:207-224. [7] BAUDIN G,MATTHEWS S,BESSUDO R,et al.. Medium Resolution Imaging Spectrometer(MERIS) calibration sequence[J].SPIE,1996,2819:141-240. [8] LABANDIBAR J Y,BAUDIN G,BAILLION Y. ALCATEL-SPACE in hyper/multispectral earth observation programs, from MERIS to SPECTRA[J].SPIE,2004,5234:232-242. [9] BARRY P S,SHEPANSKI J,SEGAL C. Hyperion on-orbit validation of spectral calibration using atmospheric lines and an on-board system[J].SPIE,2002,4480:231-235. [10] WERIJ H,KRUIZINGA B,OLIJ C,et al.. Calibration aspects of remote sensing spaceborne spectrometers[J].SPIE,1996,2820:126-137. [11] CUTTER M A,LOBB D R,WILLIAMS T L,et al.. Integration & testing of the Compact High-Resolution Imaging Spectrometer(CHRIS)[J].SPIE,1999,3753:180-191. [12] DELWART S,HUOT J P,BOURG L. Calibration and early results of MERIS on ENVISAT[J].SPIE,2003,4881:337-344. [13] FOLKMAN M,PEARLAMAN J,LIAO L,et al.. EO-1/hyperion hyperspectral imager design, development, characterization, and calibration[J].SPIE,2001,4151:45-51. [14] GAO B C,MONTES M J,DAVIS C O. A curve-fitting technique to improve wavelength calibrations of Imaging Spectrometer .(2005-04-01) .ftp://popo.jpl.nasa.gov/docs/workshops/02-docs/toc.html. [15] NEVILLE R A,SUN L,STAENZ K. Detection of spectral line curvature in imaging spectrometer data[J].SPIE,2003,5093:144-154. [16] 宋炳超,刘文清,张玉钧,等. DOAS谱线波长配准存在的问题及解决方法[J]. 量子电子学报 ,2003,17(6):680-684. SONG B CH,LIU W Q,ZHANG Y J,et al.. A method for resolving the spectra shift and squeeze in differential optical absorption spectroscopy[J].Chinese J. Quantum Electronics,2003,17(6):680-684.(in Chinese) [17] GUANTER L,RICHTER R,MORENO J. Spectral calibration of hyperspectral imagery using atmospheric absorption features[J].Appl. Opt.,2006,45(10):2360-2370. [18] LIAO L,JARECKE P,GLEICHAUF D,et al.. Performance characterization of the hyperion imaging spectrometer instrument[J].SPIE,2000,4135:254-263. [19] 卢锷,颜昌翔,吴清文,等. 空间光学遥感器环境适应性设计与实验研究[J]. 中国光学与应用光学 ,2009,2(5):364-376. LU E,YAN CH X,WU Q W,et al.. Research on adaptability of optical remote sensors in mechanical and space thermal environments[J].Chinese J. Opt. and Appl. Opt.,2009,2(5):364-376.(in Chinese)
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