Hybrid Positioning Engine Running on 5G and GNSS

Last Updated: 14/05/2024 08:05     Created at: 14/05/2024 08:05

Final Presentation of NAVISP Project EL2-114 now available:

On Thursday, May 08th, 2024, Geomatics Research & Development srl together with algoWatt SpA and Politecnico di Milano presented the results of the NAVISP EL2-114 project "HYbrid Positioning Engine Running on 5G and GNSS (HYPER-5G)". Over 50 people from industry and research institutes followed the interesting presentation and the subsequent interactive Q&A session.

The integration of Global Navigation Satellite Systems (GNSS) and 5G cellular networks holds significant promise for advancing positioning technology. Cellular positioning, introduced to address regulatory needs in 3GPP Release 15, primarily focused on emergency calls but lacked support for commercial applications. However, with the emergence of 3GPP 5G Release 16, enhancements such as dedicated Positioning Reference Signals (PRSs) are paving the way for improved cellular positioning, enabling applications like geolocation and augmented reality.

In this context, HYPER-5G explored the synergy between GNSS and 5G technologies. Leveraging 5G broad coverage and existing infrastructure, particularly advantageous in urban areas where GNSS signals may face challenges, the project aimed to overcome current positioning limitations. Specifically, it focused on developing algorithms and software to establish a precise positioning engine capable of harnessing observations from both GNSS and 5G networks.

The system architecture providing precise positioning to users through a hybridization of GNSS and 5G involves several components: First, GNSS satellites provide observations to both end-user devices and the 5G communication infrastructure. The 5G infrastructure i provides observations over 5G signals for positioning. Last this architecture requires user hardware equipped with both GNSS and 5G equipment, seamlessly integrated into the same device.

HYPER-5G conducted various experiments in Milan, Italy, utilizing specialized equipment to gather real GNSS and 5G signal data. The project team employed a mix of GNSS receivers, including low-cost ones, and 5G scanners for data collection. These data were processed using a hybrid Extended Kalman Filter (EKF). The developed algorithms and software enabled the joint processing of 5G Time of Arrivals (ToAs) and GNSS pseudorange observations, resulting in significantly improved positioning accuracy. 

Thus, the project resulted in the development of a "hybrid" positioning algorithm and its corresponding software implementation. This combination leverages multi-constellation GNSS PPP-RTK-augmented observations alongside range and angle observations derived from the transmission and reception of 5G signals. Thus, with the support of NAVISP, the consortium demonstrated that this hybrid approach achieved higher positioning accuracies. In detail varying levels of positioning accuracy were achieved. In static mode, the 5G-only approach achieved approximately 4m (2D error), while the Hybrid 5G-GNSS method reached about 1-3m. In kinematic mode, the 5G-only approach yielded around 20m (2D error), whereas the Hybrid 5G-GNSS method achieved roughly 1-4m. This offers redundancy and resilience in GNSS-denied environments. The research highlighted how important synchronization among 5G base stations and the impact of multipath effects are on positioning accuracy.

The project was part of NAVISP Element 2, which aims to maintain and improve the capabilities and competitiveness of the participating States' industry in the global market for satellite navigation and, more broadly, PNT technologies and services.

More detailed information can be found in the slides of the Final Presentation and on the Hyper-5G Website.