星载遥感器在轨运行中受到外太空环境以及遥感器自身特性衰变的影响,辐射特性会发生变化.为确保星载遥感数据能真实地反映被观测地物目标特征及其变化规律,需要定期对星载遥感器进行在轨辐射定标.环境小卫星超光谱成像仪(HJ1A/HSI)由于缺乏配套的星上定标系统,基于场地定标的方法难以满足高频次定标的需求.以EO-1/Hyperion为参考遥感器,以HJ1A/HSI为待定标遥感器,通过反卷积方法对两成像光谱仪光谱通道之间进行精确光谱响应匹配,消除波段设置的差异性,显著降低了HSI定标系数的不确定度.基于本定标方法得到的HSI 115个波段的绝对定标系数中,Band 1至Band 60之间的定标系数的不确定度稳定在5％～8％,除760 nm附近的氧气吸收波段与940 nm附近的水汽吸收波段外,其余波段的定标系数的不确定度为7％～18％,随着波长的增加,不确定度增大.与传统波段匹配方法相比,提高了约50％的精度,该定标精度基本可以满足遥感数据定量化应用的需求.该方法解决了在轨星载成像光谱仪光谱通道设置差异大、交叉定标精度低,难以实用的问题,为星载成像光谱仪高频率更新辐射定标数据提供了一种有效方法.%The present paper analyzed the influence of the pinhole diameter, grating parameters, CCD pixel size, prism parameters, system aberrations and found that the first three are the main factors, and then deduced the mutual restraint relationship among them. On this basis, a portable high-resolution echelle spectrograph was designed. Applying this design, aberration was fully corrected and spectral resolution achieved the demand. With the Hg lamp calibrated and restored, the actual resolution gets up to 0. 038 ran which is significantly better than target (0. 05@200 nm), while the ordinary grating spectrometers need 500 mm focal length to achieve this resolution. From this result, the advantages of the portable echelle spectrograph are fully demonstrated.
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