The purpose of the study on which this paper is based was to establish whether there was a maritime requirement for a Global Navigation Satellite System (GNSS) integrity monitoring and warning service in UK and Irish waters, and, if so, how best it could be established and operated.

The scope of the study extended to all maritime users: merchant ships; fishing vessels; pleasure craft; and all aspects of the voyage: harbour/harbour approach; coastal and ocean passage.

It has been assumed that the United States Global Positioning System (GPS) would be the system adopted, since it is the closest to an operational state. However, most of the technical considerations would apply equally to the Russian GLONASS or any future replacement system under international control.

The views expressed are those of the author, and should not be taken to represent the policies of the Department of Transport or any of the other bodies mentioned.