A data-driven multipath error mitigation method for PPP-RTK and its application in deformation monitoring

doi:10.11947/j.AGCS.2025.20250196

Abstract

Abstract:

Accurately extracting the multipath errors on the modeling day is a crucial prerequisite for effective multipath mitigation in PPP-RTK. However, due to the accuracy of correction products and parameter estimation errors, PPP-RTK observation residuals often contain other unmodeled errors that lack spatiotemporal repeatability. These errors are mixed with multipath errors in the frequency domain, making them difficult to remove using conventional frequency-domain-based filtering methods, and if not properly addressed, may be incorporated into the multipath correction model, thereby degrading positioning accuracy. This paper proposes a data-driven multipath error mitigation method. First, the observation residuals are decomposed into a series of reconstructed components (RCs) using the multi-channel singular spectrum analysis (MSSA) technique, where each RC represents an underlying spatiotemporal signal mode. Then, the inherent spatiotemporal characteristics of different error components are utilized to identify and extract the multipath error and establish a multipath correction model. Moreover, to accommodate the special requirements of dynamic monitoring stations, we replace the traditional mean positional parameter with one that reflects the actual deformation trend of the station during residual extraction. Results from PPP-RTK experiments conducted on a real landslide scenario demonstrate that the proposed method achieves positioning accuracies of 0.89, 0.99 and 2.40 cm in the east, north, and up directions, respectively. Compared to traditional wavelet-based sidereal filtering (SF) methods, the proposed approach improves positioning accuracy by approximately 8, 9 and 7 percentage points, respectively.

Key words: multipath errors, dynamic deformation monitoring, PPP-RTK, sidereal filtering, MHM

CLC Number:

P228

Xinrui LI, Xuanyu QU, Qin ZHANG, Bao SHU, Lingen MENG, Hao XU, Shuangcheng ZHANG, Guanwen HUANG, Hanwen WU, Li WANG. A data-driven multipath error mitigation method for PPP-RTK and its application in deformation monitoring[J]. Acta Geodaetica et Cartographica Sinica, 2025, 54(12): 2168-2181.

Figures/Tables 12

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待估参数	表达式
	dt_r+d_IF，_r/c



	M_Pi+ε_Pi
	M_Li+ε_Li

分量	E		N		U
分量	平均/cm	提升/（%）	平均/cm	提升/（%）	平均/cm	提升/（%）
未滤波	1.20	—	1.25	—	2.88	—
WT-SF	0.99	17.5	1.10	12.0	2.64	8.3
MHM	0.93	22.5	1.03	17.6	2.56	11.1
MSSA	0.89	25.8	0.99	20.8	2.40	15.3