Marine Differential GPS Service
The General Lighthouse Authorities' (GLAs) public marine Differential Global Positioning System (DGPS) is a satellite based navigation system. It is the newest element of the mix of visual, audible and electronic aids to navigation provided by the three General Lighthouse Authorities of the UK and the Republic of Ireland under their Marine Navigation Plan (MNP).
The MNP resulted from widespread consultation with the maritime community on the requirement for Marine Aids to Navigation into the 21st Century. The Plan has been devised to ensure the ongoing provision of a satisfactory, economical and reliable aids to navigation service to meet the changing requirements of all classes of mariner.
The DGPS is a network of 14 ground-based reference stations providing transmissions with coverage of at least 50 nautical miles around the coasts of the United Kingdom and the Republic of Ireland. It is an open system - available to all mariners - and is financed from light dues charged on commercial shipping and other income paid into the General Lighthouse Fund.
DGPS can assist the safe passage of all classes of vessels from cargo ships, cruise liners and fishing vessels to small yachts, by :
* monitoring the integrity of the US NAVSTAR Global Positioning System (GPS)
* improving accuracy for safe navigation in waters where the freedom to manoeuvre is restricted.