The DGPS service was established in Norway over 25 years ago to meet the demand at that time for more accurate GPS positioning signals for ships in Norwegian waters. The service in Norway consists of 12 stations along the coast that measure GPS signals, calculate position deviations, and broadcast corrections and alerts to ships.
Why Discontinue?
Since the service began, GPS signals and receivers on ships have been improved in several ways, reducing the need for this service today. DGPS is not an independent backup system to GPS, and if GPS satellite signals are blocked, for example by jamming, ships will not be able to navigate using DGPS alone. Although DGPS has been modernized over the years, it has reached its technical lifespan and lacks operational reliability. To continue operating, substantial technical renewal of the infrastructure would be necessary.
The Norwegian Coastal Administration has examined the performance of navigation signals in Norwegian waters over several years. During 2023, a user survey among navigators sailing in Norwegian waters was conducted and consultations regarding the proposed discontinuation of the DGPS service were held. The assessment by the Norwegian Coastal Administration is that the performance of GPS and the DGPS service, together with the user survey and consultation, support discontinuing the service.
Improved GPS
GPS receivers on ships have been much improved in recent years. Receiver Autonomous Integrity Monitoring (RAIM), assessing GPS signal accuracy, has been included since 2003 in new GPS receivers approved for use on ships. The satellite-based service, European Geostationary Navigation Overlay System (EGNOS), has been operational since 2009 and is included in most new GPS receivers for ships. EGNOS provides GPS corrections similarly to the DGPS service. EGNOS has recently been expanded with the EGNOS Safety of Life Assisted Service for Maritime, with improved adaption to maritime use. This new service is expected to be incorporated in future GPS receivers for ships. Additionally, the European satellite navigation system Galileo is expected to be approved for full operation by 2026, with the system included in new GPS receivers approved for use on ships thereafter.
What Should Shipping Companies and Navigators Do?
The DGPS-service will be terminated January 27, 2026. The Norwegian Coastal Administration recommends that shipping companies with vessels operating in Norwegian waters and using the DGPS service assess whether the discontinuation creates any needs for adjustments.
Navigators on ships are advised to consult user documentation on their GPS receivers and ensure that RAIM functionality and EGNOS are utilized when sailing in Norwegian waters. EGNOS's service area includes all Norwegian sea areas southward of 72 degrees north.
It is also recommended to employ GPS receivers using both the GPS-system and the European Galileo system, and RAIM and EGNOS Safety of Life Assisted Service for Maritime, at new ship constructions or renewals of GPS receivers.