Onboard calibration technologies for hyper-spectral imager

The Hyper-spectral Imager (HSI) is a kind of new optical remote sensor that can simultaneously obtain imaging and spectral information of ground targets. Onboard calibration is the basis for space-borne HSI to obtain accurate quantified spectral imaging data. In this paper, we firstly presented the principles of onboard calibration for HSI; then made a classification of the onboard calibration technologies according to the different calibration references, and reviewed the onboard radiometric and spectral calibration technologies for HSI; finally, made an expectation to the development of the onboard calibration technologies in the future. Absolute radiometric calibration has already been the basic requirement of the radiometric calibration of HSI, and solar radiance will gradually take place of onboard lamps to be the absolute radiometric calibration reference. The calibration accuracy and reliability will be greatly enhanced by the combination of multi calibration technologies based on different calibration references. With the enhancement of the calibration accuracy, ground spectral calibration assembly will be used in the space and detector-based radiometric calibration systems will be generally taken into application in the onboard radiometric calibration.