基于谱线匹配技术的星载成像光谱仪星上光谱定标方法研究

摘要

介绍了一种基于谱线匹配技术的星上光谱定标方法，该定标方法选取大气吸收线作为匹配谱线，采用相关系数法作为匹配结果判定条件标进行光谱定标。为模拟星上定标过程，将谱线匹配技术应用于振动试验后的成像光谱仪，振动试验可以模拟成像光谱仪在升空过程中受到的振动。星上光谱定标包括成像光谱仪分辨率的确定、面阵探测器光谱维和空间维像元中心波长的定标。由定标结果可知，振动试验后光谱仪分辨率为0.40 nm ，与振动试验前相比没有发生变化；光谱维像元中心波长向长波偏移0.08 nm （小于一个像元）；空间维像元光谱弯曲（光谱smile）向短波方向弯曲，最大弯曲值为0.96 nm ，近似于振动试验前光谱弯曲值。由此验证了谱线匹配技术进行星上光谱定标的可行性。%Spectral calibration of space‐born imaging spectrometers based on spectrum‐matching technique is presented ,which a‐dopts atmospheric absorption lines as the matching lines ,and chooses correlation coefficient method as the criteria .In order to simulation the onboard spectral calibration ,the spectrum‐matching technique is applied on the imaging spectrometers that after the vibration test .The vibration test is able to simulation the launching .The spectral resolution ,center wavelength of two‐di‐mensional pixel is determined during onboard spectral calibration .As the calibration results show ,the spectral resolution of ima‐ging spectrometers after the vibration test is 0.40 nm ,it is the same comparing to the value before the vibration ,the wavelength shifts 0.08 nm towards the long wave for the spectral pixels ,and the spectral smile is determined for all spatial elements ,which shifts towards the short wave direction ,with the max smile value is 0.96 nm ,the result is similar to that before the vibration . As a result ,the spectrum‐matching technique is tested and verified .