Evaluation and analysis of stochastic modeling of BeiDou GEO/IGSO/MEO satellite observation

• Main Authors: GAO Weiguang, MIAO Weikai, CHEN Gucang, JIA Song
• Format: Article
• Language: zho
• Published: Surveying and Mapping Press 2020-12-01
• Series: Acta Geodaetica et Cartographica Sinica
• Subjects: stochastic model; cross correlation; time correlation; beidou system; quality control
• Online Access: http://xb.sinomaps.com/article/2020/1001-1595/2020-12-1511.htm

Firstly, the importance of stochastic model in precise positioning is demonstrated from the perspectives of parameter estimation, accuracy evaluation and quality control. Then, based on the single-difference functional model, the rigorous variance component estimation (VCE) method is used to allow the estimation of satellite-specific variances, cross correlations between two arbitrary frequencies, as well as the time correlations for phase and c+ode observations per frequency. The influence of the stochastic model on baseline precisions and the overall statistics was subsequently analyzed. The results show that the observation precisions of the BeiDou user receiver are overall elevation-dependent for phase and code of all frequencies. It is recommended to use the elevation-dependent exponent weighting model; there are different degrees of correlation between the three frequency phase observations, and the cross correlation between other types of observations is not obvious. The time correlation between phase and code observations of different frequencies is obvious, and attention should be paid to high-precision positioning. Furthermore,the baseline precisions that used the correct stochastic model match the theoretical ones very well for the three baseline components. The paper provides support for users to correctly understand the three types of satellite observation of the BeiDou system and correctly apply the BeiDou system.