GNSS-IR retrieval method with consideration of tidal periodicity of sea level
Sea level monitoring is important for coastal production and safety,marine monitoring and analysis.With the devel-opment of Global navigation satellite systems(GNSS),a new technology called GNSS-interferometry reflectometry(GNSS-IR)has been demonstrated can be used to monitor coastal sea level.The vertical distance between reflecting surface and anten-na named reflector height(RH)can be estimated from the observations,and then the sea level can be retrieved.There is an important error named height variation error in this technique causing by the movement of sea surface.However,the classical correction method cannot calculate RH rate accurate and subsequently cannot effectively correct the error.So,this paper pres-ented a GNSS-IR combination method with the consideration of tidal periodicity of sea level.Based on the tidal wave coeffi-cient,the RH rate of change can be predicted and incorporated into the GNSS-IR combination equation to better correct the height variation error.The paper conducted experiments using three international GNSS stations.Compared with sea level measurements,the results showed that the accuracy of the GNSS-IR combined retrievals were improved by approximately 1.2 cm when tidal wave characteristics were considered than when were not,and they achieved an accuracy improvement of 20％to 70％compared to classical algorithms.The results indicate that the improved algorithm corrects height variation errors more effectively by predicting RH rate of change at different times through tidal analysis.
万方数据
维普
