Polish GNSS researchers detected GPS interference in the Baltic Sea with characteristics beyond commercial-grade jamming, originating from mobile maritime sources rather than a fixed land base. Over six months from June 2024, 84 hours of interference were recorded near Gdynia Maritime University, causing navigation errors up to 100 feet. Multi-constellation jamming affected GPS, GLONASS, BeiDou, and Galileo, switching from broad jamming to multi-tone interference starting October 2024. The interference likely came from powerful ship-mounted jammers aboard vessels in international waters, consistent with known Russian 'shadow fleet' equipment. The disruption impacted ground-level maritime navigation but not airborne ADS-B systems. Researchers call for a terrestrial GNSS sensor network with geolocation to identify offending vessels and enforce action.

Polish GNSS researchers detected GPS interference in the Baltic Sea with characteristics beyond commercial-grade jamming, originating from mobile maritime sources rather than a fixed land base. Over six months from June 2024, 84 hours of interference were recorded near Gdynia Maritime University, causing navigation errors up to 100 feet. Multi-constellation jamming affected GPS, GLONASS, BeiDou, and Galileo, switching from broad jamming to multi-tone interference starting October 2024. The interference likely came from powerful ship-mounted jammers aboard vessels in international waters, consistent with known Russian 'shadow fleet' equipment. The disruption impacted ground-level maritime navigation but not airborne ADS-B systems. Researchers call for a terrestrial GNSS sensor network with geolocation to identify offending vessels and enforce action.