| The attenuation of radiation response will occur in the on-orbit operation of space remote sensing instruments,resulting in insufficient accuracy of feedback data.The accuracy of remote sensing data is directly related to the scene and model it applies.Therefore,on-orbit calibration of remote sensing instruments highlights its importance and necessity,which is a major problem in recent years and also a problem that needs to be solved.In order to solve the problem of uniform radiometric calibration of multisatellite remote sensing instruments,a stable calibration source is needed.Moon calibration is a new calibration method proposed in the 21 st century.Moon brightness is suitable,reflectivity is stable,and the surface is free of atmosphere,which makes it a hot spot in orbit calibration in recent years.Long-term observation of the moon and the establishment of the relationship between the radiation response of remote sensing instruments and the standard quantity can guarantee the accuracy of remote sensing data.At present,there is no accurate lunar radiation standard in the world,and due to the influence of the moon phase,the balance movement,the distance between the sun and the earth and the moon,the data obtained directly from the lunar observation cannot be used efficiently.Therefore,the key is to design high-precision lunar radiation model.The ROLO model of the United States is mostly used as the standard model in the world,and the absolute uncertainty of the ROLO model is 5 % ～ 10 %.In order to build a high-precision lunar irradiance model with independent intellectual property rights in China,a large number of observation data are needed.Ground-based imaging spectrometer can obtain high-precision short-wave infrared spectral radiation data of the moon covering large moon phase and all-day translation through high-frequency and long-term observation of the moon,and these data are stored in a database to improve data quality and accumulate experiments for highprecision lunar models with independent intellectual property rights in China.The main contents of this thesis are:1.Based on the need of high-precision lunar radiation measurement,the automatic observation experiment of ground-based lunar imaging spectrometer is carried out.The ground-based lunar observation system is composed of LOIS(Lunar Observation Imaging Spectrometer),star-searching mirror with large field of view,equatorial instrument and industrial computer.In the early stage,the full experimental site and experimental scheme are investigated.Finally,the ground-based lunar automatic observation system is built in Lijiang,Yunnan.The working spectrum of the imaging spectrometer is 1000nm-2400 nm.2.In order to track the moon accurately,a slit spectrometer observation method based on the turntable of the equator is proposed.The method realizes the automatic tracking and positioning of the moon by means of a large field of view star search mirror.The minimum circumcircle algorithm is used to extract the position of the center of the moon and the conversion of the latitude and longitude coordinates of the image.The synchronization of the internal coordinate system of the equator is realized to ensure the accuracy of automatic observation.3.Based on the high-precision lunar radiation measurement data,the laboratory calibration and performance evaluation of the lunar imager were carried out,mainly including spectral calibration test,spectral resolution test,signal-to-noise ratio test and radiation uncertainty test,which ensured the accuracy of the ground-based lunar automatic observation experiment.4.In order to eliminate the geometric error of the lunar hyperspectral image in the observation process,the push-broom mode was corrected,and the collected original data were preprocessed.In view of the distortion degree of the collected lunar image,a correction method of the lunar drift angle and the correction method of the lunar image over-sampling were proposed. |
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