A Time Synchronization Algorithm Based on Correlation Analysis in GNSS/INS Integrated Navigation

In the intelligent unmanned vehicles swarm systems, multi-sensor integrated navigation is commonly used to provide reliable positioning solutions. To correctly fuse the measurements from multiple sensors, their time should be precisely synchronized. Aiming at the problem of multi-sensor time synchronization, this paper proposes a time synchronization algorithm based on correlation analysis between velocities or accelerations measured by different sensors. Taking the Global Navigation Satellite System (GNSS) and the inertial navigation system (INS) as experimental object, a field test was conducted to verify the performance of the proposed algorithm in a GNSS/INS integrated navigation system. The results show that the algorithm can indeed calibrate the time transmission delay or clock source inconsistency between GNSS and INS within a certain range of misalignment. The accuracies of calibration are 95.71% and 99.64% under velocities and accelerations correlation analysis, respectively.