A model-based Signal-In-Space interface specification to support the design of Galileo receivers

The design and development of Galileo receivers will be a key factor to determine the market approach and penetration. The massive use of the Galileo services will be impacted, as well as the estimated economical return of the Galileo linked activities. In general, GNSS receivers use similar mathematical models for the computation of the global positioning from a standard parameter set. However, receivers design and implementation solutions are often inherently dependent on the specific parameter representations defined in the Signal-In-Space (SIS) interface specifications. In this paper, we introduce Interface Communication Modeling Language (ICML) as a model-based approach for the SIS interface specification to support the engineering of Galileo receivers. We argue that a model-based specification can potentially bring several technical benefits to the design of Galileo receivers, including support for specification communication among stakeholders, reuse and adaptation of existing GPS software and chipsets, and receiver-side multi GNSS interoperability, for example. As a result, a model-based SIS interface specification can contribute to increase the use of the Galileo services by reducing the impact of the technical factors leading to the extra costs. In the paper, we present the overall layout of the ICML language and preliminary applications. In particular, we present a simplified excerpt of a Galileo-like SIS specification and functional schema of GNSS receivers and show how the ICML-based specification can support the design of Galileo receivers. An important caveat: no endorsement is made for the use of the ICML language for the official Galileo SIS interface specification.