国产C波段SAR卫星绝对辐射定标精度验证
Absolute radiometric calibration accuracy verification of domestic C-band satellite
邓明军 1陈志远 2张过 3刘宁 2杨银4
作者信息
- 1. 湘潭大学 自动化与电子信息学院,湘潭 411105;湖南国家应用数学中心,湘潭 411100
- 2. 湘潭大学 自动化与电子信息学院,湘潭 411105
- 3. 武汉大学 测绘遥感信息工程国家重点实验室,武汉 430000
- 4. 湘潭大学 数学与计算科学学院,湘潭 411100;湖南国家应用数学中心,湘潭 411100
- 折叠
摘要
SAR图像测量地球物理参数,实现定量遥感应用,对辐射定标精度有严格要求,因此需要对SAR卫星进行辐射定标精度验证.通过雷达方程推算出雷达散射截面积、定标常数与图像DN值三者之间的关系,并利用宁夏中卫定标场有源定标器及其SAR图像做定标验证实验.实验结果表明,高分三号02星数据绝对辐射定标精度较高,其中积分法辐射定标精度为0.65dB,而峰值法定标精度为0.57dB;海丝1号卫星数据辐射定标精度为1～2dB,计算定标常数时保持相同波位可有效提高定标常数的稳定性.
Abstract
SAR images have strict requirements on the accuracy of radiometric calibration in the measurement of geophysical parameters and the realization of quantitative remote sensing applications.Therefore,the radiometric calibration verification of the SAR satellites is carried out.The relationship between the backscattering coefficient,the calibration constant and the image DN value is calculated with the radar equation,and the calibration verification experiment is carried out by using the active calibrator of Ningxia Zhongwei Calibration Field and its SAR image.The experimental results show that the absolute radiometric calibration accuracy of GF-3_02 satellite data is very high,in which the integration radiometric calibration accuracy is 0.65dB,while the peak calibration accuracy is 0.57dB;the radiometric calibration accuracy of the HISEA-1 satellite data is about 1-2dB.Maintaining the same wave position when calculating the calibration constant can effectively improve the stability of the calibration constant.
关键词
绝对辐射定标/绝对定标常数/积分法/峰值法/波位Key words
absolute radiometric calibration/absolute calibration constant/integration method/peak value method/wave position引用本文复制引用
基金项目
国家重点研发计划(2020YFA0713503)
湖南省教育厅优秀青年项目(22B0168)
出版年
2024
国家科技期刊平台
NSTL
万方数据