Method and device for on-orbit absolute radiation calibration

Abstract

The invention discloses a method for on-orbit absolute radiation calibration, which comprises the steps of: conducting root calculation on optical thickness of an aerosol; determining parameters of an MODTRAN model according to atmospheric spectral transmittance of a measured wave band; adopting the MODTRAN model with determined parameters, and calculating to obtain atmospheric spectral transmittance on a ground target-satellite path; calculating total solar irradiance on the surface of a target; and calculating entrance pupil radiance of a satellite; looking up DN values of gray scale targets on a satellite digital image, and determining absolute calibration parameters of load carried by the satellite by combining the DN values with the entrance pupil radiance corresponding to the ground target. The invention further discloses a device for on-orbit absolute radiation calibration. By adopting the method and the device for on-orbit absolute radiation calibration, the atmospheric parameter processing procedure for on-orbit absolute radiation calibration of a remote sensing satellite is simplified, and an atmospheric transmission model most accordant with the actually-measured atmospheric condition can be determined, thereby improving the on-orbit absolute radiation calibration precision of the remote sensing satellite.

Description

technical field [0001] The invention belongs to the field of satellite remote sensing applications, and relates to an on-orbit absolute radiation calibration method and device applied to satellites. Background technique [0002] In recent years, with the deepening of satellite remote sensing applications, more and more attention has been paid to the quantitative research of satellite remote sensing data, and the premise and key of the quantitative application of remote sensing lies in the absolute radiometric calibration of satellite payloads. Commonly used calibration methods in the world include: laboratory calibration before reflection, on-orbit on-satellite calibration, and on-orbit calibration using site targets after launch. At present, many optical remote sensing satellites do not have on-board calibration devices, and the laboratory calibration coefficients are affected by the vibration during the launch process, so the accuracy cannot be guaranteed. Therefore, the o...

AI Technical Summary

Problems solved by technology

The radiance method is the most accurate of the three methods, but it is rarely used due to factors such as high cost and many restrictions in the measurement process.

[0004] Using the irradiance method for on-orbit radiation calibration of optical remote sensing satellites is a common practice in the world, but in the calculation process of the irradiance method, due to the assumptions of some parameters in the atmospheric transfer model, such as etc., the calibration accuracy still needs to be improved

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