Research Of GPS-MR Algorithm In Tide Monitoring

Global warming,which leads to the melting of ice and snow in the polar regions and the rise of sea level,poses a huge threat to human society.How to effectively monitor sea level changes and predict their upward trend has become a hot topic in current research.With the rapid development of the Global Navigation Satellite System(GNSS),GNSS-based GNSS Multipath Reflectometry(GNSS-MR)technology provides a new technology for surface environmental monitoring.The application of GNSS-MR technology in tide monitoring can not only effectively use many shore-based GNSS stations along the coast,expand its use,but also obtain relative and absolute changes in sea level.This can also be used as a complement to the reservoir water level monitoring.This article starts with the relationship between signal-noise ratio(SNR)and multipath,describes the basic principle and technical means of GNSS-MR technology in water level monitoring,and verifies the reliability and validity of the algorithm through measured data.The factors affecting the accuracy of GNSS-MR water level monitoring were analyzed by experiments.By introducing an Empirical Mode Decomposition(EMD)into GNSS-MR,both the algorithm and it's stability are improved.The main research contents and innovations of the paper are as follows:1.The basic principle and detailed flow of GNSS-MR technology for tidal level monitoring are introduced in detail.The SNR interference signal,the selection of available satellites,and the selection of altitude angles are described in detail.Combined with the measured data,the GNSS-MR is verified.The effectiveness and accuracy of technology in monitoring tidal levels and its potential advantages and potential in tidal level monitoring are illustrated.The results show that the use of GNSS-MR technology can effectively expand the application scope of shore-based GNSS stations and provide new technical means for flexible and convenient monitoring of tide levels.2.Based on the measured data from the riverside stations,the differences in the monitoring accuracy of the GPS-MR technology at the tidal level and the river level were emphatically analyzed,and the relevant factors affecting river level monitoring accuracy and time resolution were analyzed in the hope that it could be used for GPS-MR.The promotion of inland waters provides a reference.3.The classical GPS-MR technology is improved by using EMD method.The corresponding SNR interference signal is directly extracted by EMD decomposition method,which effectively avoids the occurrence of a large number of outliers in the tidal level monitoring,and further improves the data utilization and stability of the algorithm.The improved GPS-MR algorithm can maintain high monitoring accuracy at high altitude angles,laying the foundation for the next stage of dynamic correction and segmentation.