A combination constellation mode of kinematic PPP with priori constraints for determining ocean tide loading displacement

To improve the efficiency of estimation of deriving OTLD parameters with higher accuracy and take full advantage of multi-GNSS data, we investigate the potential of using global ocean tide model predictions as prior constraint for GLONASS and combined GPS+GLONASS kinematic precise point positioning (PPP), analyzing one year of GPS and GLONASS data from 20 Crustal Movement Observation Network China (CMONC) sites distributed along China coast. Seven global ocean tide models predictions are employed as prior constraint in kinematic PPP. Compared with the results of GPS-only kinematic PPP with priori information constraint, the result shows that GPS+GLONASS and GLONASS can improve the accuracy of OTLD estimates more than 40% in three components over GPS. The comparison of the effect of OTLD estimates on long-period signals in position time series shows that the correction effect of the kinematic PPP with seven different priori information constraint estimates is all as same as the reference model in three components.