摘要
在Brown-Hayne模型基础上,利用迭代最小二乘算法实现了回波波形参数的重跟踪,同时利用重心偏移算法(OCOG)、阈值算法对Jason-2卫星的波形数据在中国渤海、黄海、东海、南海4个海域开展了波形重跟踪试验。试验表明,在4个海域,Brown-Hayne模型法获得的波形重跟踪结果相比较于阈值法、OCOG算法与法国空间局(CNES)公布结果最为一致,相互较差的标准差约2cm左右。50%阈值算法获得的波形重跟踪结果相比较于其它阈值精度更优,与CNES比较其标准差在3~6cm,但存在4~10cm的系统偏差。OCOG算法获得的结果存在较大误差,但其结果可作为Brown-Hayne模型解算的初始值。当卫星地面轨迹靠近大陆时,波形重跟踪获得的海面高改正量会较宽阔海域增大,其中南海区域的海面高改正量最大,可达1m,其原因可能是卫星地面轨迹经过了西沙群岛,雷达回波波形受到了一定的影响。
Three methods including offset centre of gravity retracker(OCOG),threshold method and Brown-Hayne model are evaluated in this paper.Retracking experiments were conducted for Bohai,Yellow Sea,East China Sea,and South China Sea areas using Jason-2 20 Hz Sensor geophysical data recorder(SGDR).The results show that the iterative least square method has an accuracy of 2cm,comparing favorably to the maximum likelihood estimator(MLE)method issued by CNES in the four sea area.A 50% threshold value yields superior performance than other values applied to the China seas area with an accuracy of 3~6cm and bias of 4~10cm in contrast to the MLE method.The OCOG method delivers less accurate results but this may be due to the initial value in the BrownHayne model.The correction quantity with respect to the normal tracking points increases when close to continents and islands,especially in the South China Sea,as the biggest correction is 1m;radar waveforms are affected when satellite tracks cross the Xisha archipelago.
出处
《武汉大学学报（信息科学版）》
EI
CSCD
北大核心
2015年第11期1499-1503,共5页
Geomatics and Information Science of Wuhan University
基金
国家高分辨率对地观测专项青年创新基金资助项目(GFZX04060103-7-14)
国家自然科学基金资助项目(41174017)~~
