Final Presentation available for NAVISP EL1-088 quater "Proof-Of-Concept of Advanced Navigation Algorithms Based on Factor Graph Optimization"

Last Updated:     Created at:

On the 5th of October 2026 GMV, with the partner Cranfield University, presented the results of NAVISP‑EL1-088 quater, which addresses the exploitation of Factor Graph Optimisation (FGO) in GNSS/INS navigation solutions. 

The project led to a unified framework supporting a consistent comparison between FGO and conventional WLS/EKF approaches, with the application of FGO to both code-based and carrier-phase-based positioning methodologies, including PPP and RTK.

FGO improved performance across the evaluated scenarios, receivers and processing modes, confirming the benefit of temporal graph optimization. 

The largest gains were observed in RMS and high-percentile errors, showing improved robustness against multipath, NLOS reception and degraded satellite geometry.

  1. At aggregated level relative improvements for code-based processing were 30-60% in 2D and 3D RMS and relative improvements for PPP and RTK were 25–40% in 2D and 3D. 

This was the fourth project awarded on the subject of FGO.  

The activity was fully funded by ESA NAVISP Element 1, whose objective is to innovate PNT technologies, products and services. The slides can be accessed here.