Federated Extended Kalman Filter Integrating Terrain-Referenced and Quantum Magnetometer–Aided Navigation for GNSS-Denied Environments

Jayden Dongwoo Lee, Hyochoong Bang, Minseok Choi, Deok-Young Lee, Daham Kim, Sin Hyuk Yim, Sangkyung Lee, Yoontae Hwang

Peer Reviewed

Abstract:	Global Navigation Satellite Systems (GNSS) have long served as the foundation of modern navigation; however, their reliability significantly deteriorates under jamming, spoofing, or signal blockage, as demonstrated in recent battlefield and urban environments. To ensure stable operation in such GNSS-denied conditions, alternative navigation methods such as vision-based, terrain-referenced, gravity-aided, and magnetic anomaly navigation have been investigated. While each of these methods offers distinct advantages, they also exhibit environment-dependent limitations, preventing consistent performance across diverse conditions. To address these challenges, this study proposes an adaptive fusion-based navigation framework that integrates multiple alternative navigation sensors using a federated extended Kalman filter architecture. The framework is built upon a navigation model and incorporates three types of navigation subsystems: GNSS/INS, radar altimeter–aided INS, and quantum magnetometer–aided INS. In addition, a covariance adjustment algorithm is introduced to adaptively tune the measurement noise covariance in real time based on the statistical distribution of the acquired data, thereby enhancing transition stability among sensor models. Simulation results conducted under flat-terrain and magnetic dead-zone conditions demonstrate that the proposed method maintains stable and reliable navigation performance, outperforming single-sensor alternatives. The proposed fusion approach provides a foundation for resilient navigation architectures capable of operating autonomously and robustly in GNSS-denied or degraded environments.
Published in:	Proceedings of the ION 2026 Pacific PNT Meeting April 13 - 16, 2026 Hilton Waikiki Beach Honolulu, Hawaii
Pages:	235 - 242
Cite this article:	Lee, Jayden Dongwoo, Bang, Hyochoong, Choi, Minseok, Lee, Deok-Young, Kim, Daham, Yim, Sin Hyuk, Lee, Sangkyung, Hwang, Yoontae, "Federated Extended Kalman Filter Integrating Terrain-Referenced and Quantum Magnetometer–Aided Navigation for GNSS-Denied Environments," Proceedings of the ION 2026 Pacific PNT Meeting, Honolulu, Hawaii, April 2026, pp. 235-242. https://doi.org/10.33012/2026.20639
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In