星载成像高度计双侧独立交叉定标方法  

Bilateral independent cross-calibration method of the satellite-borne imaging altimeter

作　　者：白卓 张颢馨 马纯永[1,2] 赵朝方 陈戈[1,2] BAI Zhuo;ZHANG Haoxin;MA Chunyong;ZHAO Chaofang;CHEN Ge(College of Information Science and Engineering,Ocean University of China,Qingdao 266100,China;Qingdao National Laboratory for Marine Science and Technology,Qingdao 266237,China)

机构地区：[1]中国海洋大学信息科学与工程学院,青岛266100 [2]青岛海洋科学与技术试点国家实验室,青岛266237

出　　处：《遥感学报》2023年第4期919-931,共13页NATIONAL REMOTE SENSING BULLETIN

基　　金：国家自然科学基金(编号:41906155,42030406);山东省国际合作重大专项(编号:2019GHZ023)。

摘　　要：为通过数据处理提高SWOT的观测精度,本文采用双侧刈幅独立交叉定标对相位误差和倾角误差复合输入的情况进行误差估计。本文选取横跨经度100°和纬度60°的南太平洋东部地区,以HYCOM数据作为海洋真值,根据AVISO官网提供的SWOT和Jason-2 (2016年10月前)轨道参数利用SWOT simulator进行仿真采样,进行刈幅自交叉和星下点刈幅交叉实验。实验将90%的误差校正到4 cm内,近75%的交叉点残差的标准差降到2 cm内,较解算前提升一倍,表明在仪器精度较低时,双侧刈幅独立交叉定标的方法能够科学有效估计两种误差的复合输入值,显著降低了误差水平。The Surface Water and Ocean Topography(SWOT) mission,which is scheduled to launch in 2022,will carry a Ka-band Radar Interferometer to characterize the ocean mesoscale and submesoscale circulation.The observation errors must be reduced to realize the observation target of the SWOT mission.Among the errors,the baseline inclination error caused by the inaccuracy of the baseline inclination measurement and the phase error induced by the phase mismatch in the process of interferometric imaging are difficult to eliminate.These two errors make the sea surface height measurement in the swath inaccurate and identification of the characteristics of mesoscale phenomena challenging.Therefore,the purpose of this article is to correct phase error and baseline roll error to achieve the observation goal.Both errors are linear with across track distance from nadir.Assuming that all errors,except the phase and roll errors,have met the error budget requirements,a bilateral independent cross-calibration method is proposed to detect and mitigate the two spatial coherence errors.First,the errors of the left and right swaths in the experiment are calculated.Second,the observed values in the cross region are subtracted to reduce the influence of the ocean signal.Finally,the errors are estimated based on their linear correlation with the across track distance.The orbit parameters of SWOT and Jason-2(before October 2016) provided by Archiving,Verification,and Interpretation of Satellite Oceanographic data are used for along-track sampling.The errors in the 25-day SWOT sample data are estimated by using the self-crossover and crossover(with Jason-2) methods.In the SWOT self-crossover,more than 90% of the error was corrected from 8 cm to 4 cm,and approximately 73% of the intersection-region standard deviation was adjusted from 6 cm to 2 cm.In the SWOT crossover with Jason-2,approximately 86% of the error was corrected from 8 cm to 4 cm,and approximately 55% of the intersection-region standard deviation was adjusted from 6 cm to 2 cm.Based

关 键 词：交叉定标 误差反演 相位误差 基线倾角误差 干涉成像高度计 

分 类 号：P2[天文地球—测绘科学与技术]