This paper discusses the technical, administrative and certification compatibility issues associated with satellite augmentation of GPS/GLONASS. It indicates that the Signal-in-Space specifications are central to compatibility and interoperability. ICAO Standards and Recommended Practices are a key mechanism for interoperability. The paper recommends that one standard be implemented worldwide. It also urges a mechanism for the co-ordination and management of augmentation services.

This paper and the following six papers were presented at the NAV95 Conference held in London, November 199j. The full proceedings, under the title containing 30 papers, can be obtained from the Director (£25 to Members, £35 to Non-Members).