GPS disruptions have increased over the past year in the Baltic Sea, affecting both shipping and air traffic. The Swedish Maritime Administration is developing a new navigation system based on ground stations to counter the issues. The system will be less vulnerable but not as precise, according to expert Johan Winell.
Earlier this year, the Swedish Maritime Administration raised alarms about escalating GPS disruptions primarily in the Baltic Sea. The disruptions, which the Transport Agency links to Russian territory, have increased significantly and affect navigation at sea and in the air.
To address this, the Swedish Maritime Administration, along with other countries, is developing a new system for ship positioning even during disrupted satellite signals. The system measures distances to ground stations instead of satellites and is based on classic radio navigation.
“It works by measuring distances in the same way as satellite positioning, but to ground stations instead. So it's basically classic radio navigation,” says Johan Winell, business area manager at the Swedish Maritime Administration.
The work on the system has been ongoing for ten years and is not directly linked to the recent disruptions, but it validates the investment's relevance. A key advantage is its use of existing technology, such as land-based masts and transmitters, which keeps costs low. Ships will need a new receiver to integrate the signals.
“There will be a cost for the ships because they need a new receiver that can combine these signals. On land, we'll use existing masts and transmitters and then add more information to the signals we're already broadcasting. So the costs there won't be huge,” says Winell.
The project deadline is the first half of 2027, after which production will begin. The system is considered more secure than traditional GPS, but less precise.
“But it won't be as accurate,” Winell adds.