远海实时GPS潮汐的实时精密单点定位观测

针对传统事后精密单点定位技术的时间延迟问题,该文基于IGS RTS实时数据流产品,开展了实时精密单点定位技术在远海实时GPS验潮中的应用研究.对RTS改正的实时精密卫星轨道和钟差进行了精度验证和分析,给出了RT-PPP的数据处理策略以及实时GPS验潮的基本流程;组织和实施了渤海湾船载GPS验潮试验,以压力式验潮仪数据为参考,对远距离实时GPS潮汐测量结果进行了精度分析.结果表明:①以IGS最终卫星轨道和钟差产品为参考,RTS实时精密卫星轨道在X、y、Z方向的精度(RMS)均优于3 cm,卫星钟差的精度优于0.15 ns;②采用傅里叶低通滤波方法,消除波浪对潮汐观测的影响,进一步提取潮位信息.在忽略船体姿态改正的情况下,实时精密单点定位验潮相对于压力式验潮仪结果的最大偏差优于20 cm,RMS达到7.5 cm.

Real-time GPS tide measurement in the open sea based on RT-PPP technology

In light of the lengthy delays of the traditional precise point positioning(PPP) technology,based on IGS real time service (RTS) correction products,the real-time precise point positioning(RTPPP) technology and its application in GPS real-time tide measurement over the open sea were investigated.Firstly,the data processing strategies of RT-PPP and the procedures of real-time GPS tide measurement were presented,and the accuracy of satellite ephemeris and clock offsets calculated using RTS corrections was analyzed.Then the long distance real-time ship-borne GPS tidal measurement test was carried out in the Bohai Gulf.The results showed that:①comparing with the IGS final precise satellite ephemeris and clock offsets products,the RMS of the ephemeris from RTS products in X,Y and Z components are both better than 3 cm and the RMS of clock offsets is less than 0.15 ns;②using Fourier lowpass filter method to eliminate the wave influence on tidal observation,in the case of ignoring the attitude correction,the maximum deviation of tidal level acquired using RT-PPP technology is better than 20 cm comparing with the pressure tide gauge and the RMS is 7.5 cm.