一种GNSS-R镜面反射点精确估计方法  

An Accurate Estimation Method of GNSS-R Specular Point

作　　者：俞永庆[1] 杜毅 YU Yongqing;DU Yi(Shengli Oil Field of China Petroleum and Chemical Corporation,Dongying 257000,China;School of Electronice and Information Engineering,Beihang University,Beijing 100191,China)

机构地区：[1]中国石油化工股份有限公司胜利油田分公司,山东东营257000 [2]北京航空航天大学电子信息工程学院,北京100191

出　　处：《无线电工程》2021年第2期118-122,共5页Radio Engineering

基　　金：海上平台GNSS实时综合监测技术的应用研究(319022-14)。

摘　　要：估算镜面反射点是GNSS-R应用的首要任务,目前主流的几种镜面反射点估计方法均未考虑反射点处海拔高度,使结果收敛到基准椭球面之上,严重影响镜面反射点的估算精度。以线段二分法为基础,利用Google Elevation API提供的海拔数据对镜面反射点估计结果进行修正,提出一种修正海拔误差的镜面反射点估计方法,使得镜面反射点最终收敛到实际地表。设计对比实验,分别对不同几何关系和海拔高度情况下镜面反射点估算精度进行分析。结果表明,加入海拔误差修正后的镜面反射点估计方法可输出收敛到实际地面上的镜面反射点,并且水平、竖直两方向上的精度提升幅度与反射点处海拔高度呈正相关,水平方向精度提升幅度还与GNSS卫星高度角呈负相关。Estimating the specular point is the primary task of GNSS-R applications.At present,the elevation of specular point is not taken into consideration in the most commonly used approaches of specular point estimation.The result converges on the reference ellipsoid,which seriously affects the accuracy of estimation.Based on the dichotomy of line segment,the elevation data obtained from Google Elevation API is applied to correct the estimation results.A method of specular point estimation with elevation error corrected is proposed,so that the specular point finally converges to actual earth surface.Experiments are designed to analyze the accuracy of specular point estimation under different geometric relationships and elevations.The results show that the proposed specular point estimation method with elevation error correction can output the specular point converging to the actual ground,and the accuracy improvement in both horizontal and vertical directions is positively correlated with the elevation at the reflection point,at the same time,the horizontal accuracy improvement is also negatively correlated with the elevation angle of GNSS satellites.

关 键 词：GNSS-R 镜面反射点 海拔高度 误差修正 线段二分法 

分 类 号：TN967.1[电子电信—信号与信息处理] P237[电子电信—信息与通信工程]