This paper is based on the results of the ‘GNSS Support
Task’ study for the European
Commission, DGXIII. It summarises the results of the cost benefit analysis
in terms of
coverage, accuracy and safety requirements for different types of user
and describes the most
cost-effective GNSS 2 architecture. These analyses also assume that the
overall system is
layered into wide area, regional and local systems. The future planning
of satellite navigation
is essentially driven by the wide area requirements and ensuring that these
are global and
seamless. There is some flexibility in coverage and accuracy for a wide
area system in that
it can be augmented regionally or locally if required, but it must provide
the highest level of
safety required. The paper approaches the architecture for a future navigation
system from
this safety aspect. An analysis of the chosen architecture shows that the
required safety
performance can be met. An implementation plan is described which allows
a gradual
evolution from the first system to be realized for safety critical operations
to a fully civilian
owned and operated system.
