Accuracy analysis of ocean tide loading constituent detection using GNSS positioning

Various space geodetic techniques have been developed for highly precise and cost-efficient positioning solutions. By correcting the physical phenomena near the earth's surface, the positioning accuracy can be further improved. In this study, the vertical crustal deformation induced by the ocean tide loading was accurately estimated through GNSS absolute and relative positioning, respectively, and the tidal constituents of the results were then analyzed. In order to validate the processing accuracy, we calculated the amplitude of eight major tidal constituents from the results and compared them to the global ocean tide loading model FES2004. The experimental results showed that absolute positioning and positioning done every hour during the observation time of 2 hours, which yielded an outcome similar to the reference ocean tide loading model, were better approaches for extracting tide constituents than relative positioning. As a future study, a long-term GNSS data processing will be required in order to conduct more comprehensive analysis including an extended tidal component analysis.