The European Railways Train Management System (ERTMS) - the standard train control system largely adopted in the world to ensuring the highest safety levels - foresees the adoption of GNSS localization having been recognized as one of the Game Changer technologies to improve its competitiveness. The benefits of GNSS localization are in the savings of trackside balises that today ensures the periodical calibration of the errors accumulated by the odometer. However, the challenge is to guarantee that a virtual balise generated using the GNSS will be enough resilient to Radio Frequency threats, namely intentional or unintentional jamming. Since these threats can significantly degrade the GNSS localization performance up to a denial of service influencing the train operations, a proper mitigation strategy has been studied after having evaluated the operational scenarios of the ERTMS application. Currently, no commercial anti spoofing and anti-meaconing solution has been designed for the railway context. The solution we have developed is based on an intelligent antenna array to improve the resiliency of the PVT (Position, Velocity and Time) estimation performed by the VBR (Virtual Balise Reader) cleaning the signal from jamming, and to identify and exclude spoofing attacks. Since the antenna is the vulnerable gate of GNSS signals, a pre-evaluation of the RF (Radio Frequency) signals is performed before these signals are processed by the VBR. A comprehensive set of specific attacks, potentially harming the ERTMS under operational scenarios, has been investigated. These attackers – having been simulated either on board or along the rail corridor – are taken in to account to mitigate the blockage of the GNSS signal acquisition/tracking, and spoofers and meaconers potentially undermining the correct train positioning. The proposed paper will analyze and assess the risks of GNSS interferences on the ERTMS operational scenarios and will present a novel solution to mitigate these risks based on a four elements phased array antenna resulting a suitable compromise when cost and performance are considered. This approach is able to both detect and mitigate jamming generated along the rail corridor and to detect spoofing through its DoA (Direction of Arrival) estimation. The performance of this solution have been evaluated through extensive Montecarlo simulations to reproduce many complex different attack scenarios potentially occurring in the ERTMS operative conditions and to stress the system in order to fully reach the ERTMS SIL-4 requirement implying a Tolerable Hazards Rate (THR) of 10E-9h.
Stallo, C., Salvatori, P., Coluccia, A., Capozzi, M., Gamba, G., Cianca, E., et al. (2019). Intelligent antennas for mitigating GNSS Jamming & spoofing hazards on the ERTMS train control. In Proceedings of the Institute of Navigation Pacific Positioning, Navigation and Timing Meeting, Pacific PNT (pp.478-492). 815 15TH ST NW, STE 832, WASHINGTON, DC 20005 USA : The Institute of Navigation [10.33012/2019.16818].
Intelligent antennas for mitigating GNSS Jamming & spoofing hazards on the ERTMS train control
Cianca E.;Rossi T.;Di Domenico S.;
2019-01-01
Abstract
The European Railways Train Management System (ERTMS) - the standard train control system largely adopted in the world to ensuring the highest safety levels - foresees the adoption of GNSS localization having been recognized as one of the Game Changer technologies to improve its competitiveness. The benefits of GNSS localization are in the savings of trackside balises that today ensures the periodical calibration of the errors accumulated by the odometer. However, the challenge is to guarantee that a virtual balise generated using the GNSS will be enough resilient to Radio Frequency threats, namely intentional or unintentional jamming. Since these threats can significantly degrade the GNSS localization performance up to a denial of service influencing the train operations, a proper mitigation strategy has been studied after having evaluated the operational scenarios of the ERTMS application. Currently, no commercial anti spoofing and anti-meaconing solution has been designed for the railway context. The solution we have developed is based on an intelligent antenna array to improve the resiliency of the PVT (Position, Velocity and Time) estimation performed by the VBR (Virtual Balise Reader) cleaning the signal from jamming, and to identify and exclude spoofing attacks. Since the antenna is the vulnerable gate of GNSS signals, a pre-evaluation of the RF (Radio Frequency) signals is performed before these signals are processed by the VBR. A comprehensive set of specific attacks, potentially harming the ERTMS under operational scenarios, has been investigated. These attackers – having been simulated either on board or along the rail corridor – are taken in to account to mitigate the blockage of the GNSS signal acquisition/tracking, and spoofers and meaconers potentially undermining the correct train positioning. The proposed paper will analyze and assess the risks of GNSS interferences on the ERTMS operational scenarios and will present a novel solution to mitigate these risks based on a four elements phased array antenna resulting a suitable compromise when cost and performance are considered. This approach is able to both detect and mitigate jamming generated along the rail corridor and to detect spoofing through its DoA (Direction of Arrival) estimation. The performance of this solution have been evaluated through extensive Montecarlo simulations to reproduce many complex different attack scenarios potentially occurring in the ERTMS operative conditions and to stress the system in order to fully reach the ERTMS SIL-4 requirement implying a Tolerable Hazards Rate (THR) of 10E-9h.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
