Satellite positioning is amongst the “game‐changing” capabilities foreseen in the evolution of European Rail Traffic Management System (ERTMS) to improve operational performance and reduce the cost of the overall system. In order to ensure that an enhanced ERTMS with satellite positioning is interoperable and minimises impact on the existing system, the ERTMS supply industry has been working on the realisation of a concept using GNSS to detect virtual balises.
The use of carrier phase for smoothing of code measurements (to reduce the impact of pseudorange noise) and for additional functions such as coasting, relies on robust carrier phase measurements. Carrier phase discontinuities, as a result of the challenging railway environment, have a significant impact on the integrity and availability of techniques dependent on carrier phase observations.
The objective of this activity is to assess, design and test techniques for improving robustness of GNSS carrier tracking in the railway environment for railway Safety of Life applications. The activity focuses on the use of GNSS positioning for virtual balise detection in the European Rail Traffic Management System (ERTMS).
The tasks to be performed will include:
(a) Review and consolidation of positioning requirements for virtual balise detection in ERTMS;
(b) Technology assessment and review of the state of the art for methods and techniques to improve the robustness of carrier phase tracking in the railway environment;
(c) Selection of candidate techniques and coasting concepts for implementation of a Proof of Concept;
(d) Specification, design and development a Proof of Concept implementing the selected techniques; and
(e) Experimentation and assessment of performances in a real or simulated railway environment.
The results of the activity will, amongst others, provide recommendations for suitability of techniques for railway Safety of Life applications, identifying gaps and future work.
For more information, refer to the NAVISP programme website.