The European Space Agency (ESA) has stress-tested the resilience of Europe’s GNSS infrastructure at Jammertest 2025, an open-air interference campaign staged in the Arctic. With satellite navigation underpinning aviation, emergency response, finance, energy grids and logistics, the event focused on real-world risks from deliberate and unintentional signal disruption. Organised in Bleik, Norway, the campaign brought together hundreds of specialists to evaluate how receivers and systems respond to jamming and spoofing, and to identify mitigation strategies for Galileo, EGNOS and the wider Positioning, Navigation and Timing (PNT) ecosystem.
What was tested
Jammertest simulates a broad spectrum of interference scenarios to expose vulnerabilities that may not appear in laboratory environments. Test cases spanned:
- Jamming: saturating receivers with noise-like signals to degrade or deny positioning.
- Spoofing: broadcasting counterfeit navigation signals to mislead timing and location solutions.
- Meaconing: delaying and rebroadcasting authentic signals, which complicates detection.
- Multi-source and coordinated attacks from different locations and platforms.
The 2025 edition involved equipment mounted on vehicles, drones, aircraft, helicopters and vessels, capturing performance across air, land and sea operations.
Why the Arctic venue matters
Bleik, at nearly 70° North and about 300 km inside the Arctic Circle, offers a controlled propagation environment. Mountains to the east help contain emissions and limit unintended impact on civil infrastructure, while an open coastline to the west enables over-sea scenarios for maritime users. This geography supports rigorous yet responsible field trials with authentic interference waveforms.
Scale and participation
The campaign gathered approximately 360 participants from 120 organisations across more than 20 countries, spanning academia, industry and public authorities. Coordinated by seven Norwegian government bodies with facilitator Testnor, the event provided common datasets and shared situational awareness so developers, integrators and operators could benchmark receiver performance under identical conditions.
ESA activities and data collection
ESA assessed the robustness of Galileo and EGNOS reception across a range of antennas—from mass-market smartphone-class devices to high-grade systems—both stationary and on a mobile testbed van. The agency compared novel receiver technologies developed under ESA programmes with current-generation solutions and evaluated equipment from industrial partners. More than 100 TB of data were recorded for research and are now available for replay at the ESA Navigation Laboratory to support reproducible testing of new designs. ESA also oversaw trials of new EGNOS ground receivers being developed by European industry under Horizon 2020 and Horizon Europe, aimed at improving the next generation of augmentation services.
System evolution and mitigation measures
ESA’s work aligns with European efforts to harden GNSS and deliver assured PNT. Key measures include:
- Multi-frequency signals and wider bandwidths to improve robustness and interference rejection.
- Navigation message authentication to help detect spoofing.
- Public Regulated Service (PRS) features for authorised users.
- Next-generation EGNOS augmenting both GPS and Galileo to enhance integrity and resilience.
- Complementary technologies and alternative PNT concepts for GNSS-denied environments.
Why resilience is a priority
As reported incidents of deliberate interference increase, disruptions can ripple across safety-critical and time-synchronised operations. The economic exposure from a widespread outage has been assessed in the billions of euros per day for Europe, elevating GNSS resilience to a public safety, security and industrial continuity issue. Field campaigns like Jammertest help close the gap between laboratory performance and operational reality, guiding receiver design, system features and regulatory frameworks.
