利用ChiGaM卫星星间位差反演Mascon模型OA

This study inverts a Mascon model based on inter-satellite range-rate observations from the ChiGaM satellite mission.The strategies employed during the inversion include:1)introducing piece-wise constant acceleration(PCA)parameters to mitigate the impact of force model errors in dynamic orbit determination;2)applying an empirical model that considers the 3-cycle-per-revolution(3-CPR)term to absorb low-frequency noise in the range-rate data;and 3)integrating multi-source data to con-struct the forward model and the a priori constraint matrix for parameters.Satellite data from March 2022 to December 2023 were processed to develop the Mascon model IEU-CGS-Monthly2023M.Com-parative analysis with contemporaneous Mascon products from the GRACE-FO mission shows that the mass change trends derived from our model are in high agreement with the reference models at both global and regional scales.The geoid degree errors of all models closely coincide within the domi-nant signal degree bands.In nine selected river basins,the average correlation coefficient between our model and the reference models exceeds 0.9.Overall,the performance of the proposed model is com-parable to that of the reference models.This study demonstrates high-precision Mascon inversion u-sing ChiGaM range-rate data,validates the satellite's capability to capture time-variable gravity sig-nals,and can serve as a reference for related data processing and applications.