GNSS Test Bench Calibration for Space Service Volume Applications

The Global Navigation Satellite System (GNSS), originally designed to support Positioning, Navigation, and Timing (PNT) services for terrestrial users, is becoming a fundamental backbone of the current and upcoming space applications. Effort are ongoing at international level to define an Interoperable GNSS Space Service Volume (SSV), aiming to establish GNSS PNT performances from Low-Earth Orbits (LEO) to Highly Elliptical Orbits (HEO) and beyond. The European Galileo GNSS system plays a key role, whit its navigation performance in space continuously improving through the integration of new input and tools. This paper provides insight into the activities currently carried out at the European Commission's Joint Research Centre (JRC) and aims to renovate its SSV testing capabilities. The focus is on the recently developed JRC Integrated SSV test bench (JRC-ISSVTB), allowing the assessment of SSV key performance parameters (KPI) with an improved level of representativeness. The solution integrates all available up-to-date information about the Galileo system capabilities, including antenna pattern modelling, and introduces a novel hardware-in-the-loop (HIL) based verification step. The test bench architecture and the calibration steps are described, along with the configuration implemented to customize the environment for different orbit regimes. The preliminary results presented here offer an additional reference for upcoming SSV applications and set the stage for a complete characterization of the Galileo SSV to be included in the next update of the interoperable GNSS Space Service Volume.