Real-time processing of unmodeled errors: detection, compensation, and control

doi:10.11947/j.AGCS.2026.20250501

Abstract

Abstract:

In GNSS applications, there exist unmodeled errors that cannot be effectively compensated by differencing and linear combination, empirical model correction, or traditional parameterization. These errors limit the precision and credibility of positioning, navigation, and timing (PNT). By leveraging a prior and posterior information as well as multiple indicators, and driven by both models and data, we design overall and source-specific detection methods for unmodeled errors and develop a complete significance testing procedure. Considering practical observation scenarios, we propose a resilient compensation method based on functional and stochastic models, encompassing strategies such as negligible, corrected, fixed, float, and weighted models for unmodeled errors. In combination with data quality control strategies, we further develop stochastic characterization and quality control methods considering the unmodeled errors. Experimental results demonstrate that the proposed real-time processing of GNSS unmodeled errors can effectively improve GNSS positioning accuracy and credibility. This work provides technical support for credible PNT under complex conditions and enriches the theoretical and methodological system of geodetic data processing.

Key words: unmodeled errors, significance testing, functional model compensation, stochastic model compensation, quality control

CLC Number:

P228

Bofeng LI, Zhetao ZHANG. Real-time processing of unmodeled errors: detection, compensation, and control[J]. Acta Geodaetica et Cartographica Sinica, 2026, 55(5): 776-786.

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Figures/Tables 6

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模型	定位误差/m
模型	E方向	N方向	U方向
非模型化误差免补模型	0.675 3	0.999 6	2.157 7
非模型化误差改正模型	0.471 9	0.629 4	0.786 1
非模型化误差加权模型	0.248 2	0.240 8	0.470 1

模型	定位误差/m
模型	E方向	N方向	U方向
非模型化误差免补模型	0.301 9	0.759 4	3.240 7
非模型化误差改正模型	0.264 4	0.988 3	0.580 3
非模型化误差加权模型	0.171 0	0.047 0	0.204 0