关键词: 光学卫星, 响应一致性, 相对辐射定标, 暗电流定标, 星上定标, 在轨均匀场地定标, 统计定标, 偏航辐射定标

Abstract:

The relative radiometric calibration of optical satellite sensors minimizes the inconsistency of linear or non-linear responses of the sensor detectors with different incident radiances. It is a prerequisite of various types of high-quality remote sensing products. The response of on-orbit sensor changes with time due to factors such as launch induced vibration, space environment changes, and the sensor degradation. However, both the one-time relative radiometric calibration and single relative radiometric calibration methods cannot guarantee the consistency in responses of satellite sensors at a specific time. Therefore, the normalized on-orbit radiometric calibration method with high frequency and high precision for satellite sensors is necessary for better applications of remote sensing products. In this study, we focused on the image radiometric calibration of the whole life cycle of optical satellite sensors, and the high-frequency, high-precision, wide or full dynamic range on-orbit relative radiometric calibration methods. Also, we summarized the existing accuracy evaluation methods of relative radiometric calibration methods as well as their application scenarios. In our study, the LJ1-01 nighttime satellite images were used to verify the dark current and uniform field calibration methods. The Zhuhai1 group 02 hyperspectral satellite images were used to verify the statistical calibration and yawing radiometric calibration methods as well as the normalized radiometric calibration method integrated by a variety of calibration methods. Our results show that the stripe coefficient was less than 0.25%, with a higher relative standard deviation of the images (3.00%) than images processed by each individual evaluation method. The normalized radiometric calibration method integrated by various calibration methods maximizes the advantages of individual calibration methods and is capable of high precision on-orbit calibration for common sensors, which further guarantees the quality of remote sensing products and meets the requirements of quantitative application.

Key words: optical satellites, response consistency, relative radiometric calibration, the dark current calibration, the on-board calibration, the uniform sites calibration, the statistical calibration, the yaw calibration