潮位变化的高精度监测一直是全球海平面观测系统、海洋环流和全球气候变化研究领域关注的热点问题之一。随着GNSS研究与应用的不断深入,近年来基于多路径效应的GNSS-MR技术已逐步成为一种新兴的遥感手段,即利用测量型GNSS站进行地表环境(植被、土壤湿度、雪深、潮位、火山活动等)监测。通过分析由多路径引起岸基GNSS站SNR值的变化特性,本文给出了基于SNR观测值的GNSS-MR技术监测潮位变化的反演原理。利用布设在美国华盛顿州Friday Harbor海港岸边的CORS站SC02实测观测数据对潮位变化监测进行了反演分析,并与该站相距359 m的验潮站数据进行了对比分析,两者较差均值约为10 cm左右,两者的相关系数均优于0.98。试验结果分析表明基于岸基CORS站的GNSS-MR技术在一定程度上可用于实时、连续的潮位变化监测,同时也说明岸基CORS站在一定程度上可作为验潮站的补充,进一步拓展GNSS在海洋遥感领域的应用范围。
Precise monitoring of tide variation is the most of issues in the fields of Global Sea-level Observation System,ocean circulation and global climate change research. With the deepening research and rapid application of GNSS,GNSS-MR based on multipath has gradually become a new means of remote sensing for ground environment( vegetation,soil moisture,snow depth,sea level,volcano and so on) with geodetic GNSS station. By analyzing the characteristics of the onshore GNSS SNR data which is caused by multipath,the inversion principle of GNSSMR technology based on the SNR data to detect tide variation is given in this paper. The onshore GNSS station of SC02 which is located in Friday Harbor,Washington state of United States,are used to retrieve tide variation. The retrieval result is consistent with the tide gauge which is only 359 m to the GNSS station. The bias is about 10 cm,and the correlation coefficient is better than 0. 98. Preliminary results show that GNSS-MR technology based on onshore CORS station to some extent could be real-time and continuously used to monitor the tide variation. What's more,onshore GNSS stations could be a powerful supplement for tide gauge and be used to extend GNSS application in marine remote sensing field.