GPS Cycle Slip Detection Considering Satellite Geometry Based on TDCP/INS Integrated Navigation

Area of Science:

• Navigation Systems
• Geomatics Engineering
• Signal Processing

Background:

• Carrier phase cycle slips degrade Global Positioning System (GPS) accuracy.
• Inertial-aided GPS (INS/GPS) integration offers enhanced navigation performance.
• Robust cycle slip detection is crucial for reliable INS/GPS solutions.

Purpose of the Study:

• To develop an effective carrier phase cycle slip detection algorithm for inertial-aided GPS.
• To leverage satellite geometry and integrated navigation solutions for improved detection.
• To validate the proposed method through simulations and real-world experiments.

Main Methods:

• Utilized a tightly coupled Time Differenced Carrier Phase (TDCP) and Inertial Navigation System (INS) integration.
• Compared GPS carrier phase measurements (satellite-difference and time-difference) with integrated solution range estimates.
• Employed satellite geometry information to enhance range estimation accuracy.
• Used filter covariance from the TDCP/INS to establish cycle slip detection thresholds.

Main Results:

• The proposed algorithm successfully detects carrier phase cycle slips.
• Satellite geometry significantly improves range estimation performance.
• The covariance-based thresholding effectively determines cycle slip occurrences.
• Both simulation and vehicle-based experiments confirmed the algorithm's efficacy.

Conclusions:

• The presented method provides a reliable approach for carrier phase cycle slip detection in INS/GPS.
• Integration of satellite geometry and INS/GPS data enhances navigation solution integrity.
• The algorithm offers a cost-effective solution by avoiding hardware modifications.