Vector tracking loop of shipborne satellite navigation receiver based on Kalman filter-divided difference filter for anti-interference enhancement

Abstract

Due to the complex and ever-changing maritime environment, ships heavily rely on stable and reliable navigation systems during their voyages to ensure safe and efficient navigation. However, during maritime navigation, satellite navigation signals are often subject to interference and obstruction, leading to degraded positioning accuracy or untrustworthy navigation data. To address the pressing need for high-precision and reliable navigation in maritime applications, this paper proposes a bidirectional smoothing filter vector tracking loop (VTL) structure based on a combination of Kalman filter (KF) and a Divided Difference filter (DDF). This approach enhances the responsiveness of the Kalman filter under high-noise conditions, and significantly improves the accuracy and robustness of the navigation system through bidirectional collaborative filtering. In practical shipborne navigation experiments, the proposed method was compared with the traditional Scalar Tracking Loops (STL), traditional VTL, and KF-based VTL approaches. The results demonstrate that the proposed method offers significant improvements in horizontal positioning and velocity accuracy. Compared with the KF-based VTL method, the proposed approach achieved an 83.20% enhancement in the positioning accuracy and a 60.00% improvement in the horizontal velocity accuracy.