The TACTIC project's primary benefit to the GNSS user community lies in raising awareness of GNSS threats at critical infrastructure.
TACTIC Creating awareness of Galileo PRS at critical infrastructures
Global Satellite Navigation Systems (GNSS) rely on the Time Difference of Arrival (TDOA) principle to furnish positioning and timing data to a wide array of users. Given the substantial distances between satellites and users, the system’s integrity may be compromised when signals on the same frequencies as those used by GNSS are intentionally broadcast. This interference can be categorized into two distinct types: spoofing and jamming.
Spoofing and Jamming
Jamming involves the deliberate transmission of interfering signals, and significant research and evidence regarding jamming have accumulated over time. In contrast, there is a need to emphasize awareness about the threats posed by spoofing within the navigation community and among GNSS user groups. Spoofing endeavors to deceive the GNSS receiver’s estimation of position and timing data by broadcasting signals that mimic GNSS signals. A spoofing device leverages the comprehensive documentation of open-service GNSS signals and can broadcast perfectly modified signals.
To some extent, open-service GNSS user receivers (e.g., those with receiver autonomous integrity monitoring) and applications possess inherent resistance to spoofing. However, these countermeasures have not undergone testing against realistic spoofing attacks. Encrypted GNSS signals, such as those employed by the Galileo PRS service, are inherently more resilient to spoofing due to the secrecy of their signal structure.
Intentional falsification of GNSS
The intentional falsification or disruption of GNSS signals poses a significant concern for the GNSS user community, especially for critical infrastructure entities. There have been limited experiments involving spoofing attacks, including safeguarding against hostile UAVs. These experiments entail setting up target GNSS receivers and using an off-the-shelf GPS/Galileo L1/E1 spoofing device to transmit spoofing signals over the air. Commercial jamming devices are also considered.
Effectiveness of GALILEO PRS
The envisioned spoofing scenarios encompass controlled landings of UAVs, deceiving smartphone navigation, and disrupting the time synchronization of electrical power networks. Simultaneously, a PRS-like signal will be broadcast from a pseudolite and received alongside the open-service satellite and spoofing signals. This setup aims to evaluate the effectiveness of future Galileo PRS receivers in countering these threat scenarios.
The project team possessed the requisite expertise to design, implement, and execute such demanding experiments. This research work was mutually benefit the team, enhancing their competence and stature within the scientific community and market.
The TACTIC project’s primary benefit to the GNSS user community lies in raising awareness of these threats and providing a more accurate assessment of their likelihood. By collaborating closely with relevant stakeholders, the dissemination of TACTIC results were optimized.
From a technological perspective, the project also involved the development of software-defined GNSS signal transmission technology, which may eventually be commercialized as a spoofing device, a GNSS pseudolite, or a GNSS RF simulator. Additionally, an existing GNSS receiver was subjected to testing to evaluate its resilience against spoofing, and recommendations were offered regarding the identification of spoofing/jamming attacks and the most effective countermeasures.