PPP Sliding Window Algorithm and Its Application in Deformation Monitoring

Area of Science:

• Geodesy
• Geophysics
• Earthquake Engineering

Background:

• Precise Point Positioning (PPP) offers advantages over relative positioning for deformation monitoring by eliminating the need for reference stations.
• Traditional PPP accuracy is limited to cm-dm levels due to observation errors, insufficient for high-precision monitoring.
• Stationary observation sites can provide valuable a priori constraint information for positioning.

Purpose of the Study:

• To develop and validate a novel sliding window-based PPP algorithm for enhanced positioning accuracy.
• To assess the algorithm's capability in detecting seismic vibrations and providing early-warning alerts.
• To demonstrate the feasibility of the new PPP algorithm for real-time earthquake monitoring.

Main Methods:

• Implementation of a new PPP algorithm incorporating a sliding window approach.
• Processing of International GNSS Service (IGS) tracking station data using both traditional and new PPP algorithms.
• Utilizing an earthquake simulation platform to test the algorithm's response to seismic events.
• Analyzing observed data from the Wenchuan earthquake.

Main Results:

• The new sliding window PPP algorithm demonstrated improved positioning accuracy compared to the traditional method, particularly in the elevation direction.
• The algorithm successfully detected vibration changes on a reference station during simulated earthquake events.
• Experimental results from the Wenchuan earthquake confirmed the algorithm's effectiveness in monitoring real seismic activity.

Conclusions:

• The proposed sliding window PPP algorithm significantly enhances positioning accuracy for deformation monitoring applications.
• The algorithm is capable of detecting seismic vibrations and has potential for real-time earthquake monitoring and early-warning systems.
• This method offers a feasible solution for high-precision monitoring of dynamic geohazards.