With the advent of new constellations, signals and frequencies, the reference stations are expected to face a major evolution by incorporating multi-frequency capabilities and adopting the multi-constellation concept, while including also more demanding requirements in terms of robustness against signal deformations, spoofing, multipath and interferences. This opens a clear business opportunity for a new generation of reference stations needed to comply with the new scenario of GNSS navigation programs. The European Geostationary Navigation Overlay Service (EGNOS) is Europe’s regional Satellite-Based Augmentation System (SBAS) that is used to improve the performance of GNSS such as GPS and Galileo. EGNOS will experiment a major evolution by 2020, EGNOS V3, including the fulfilment of the SBAS L1/L5 standard, expansion to dual-frequency and evolution towards a multi-constellation concept. The Ranging Integrity Monitoring Stations (RIMS) are expected to incorporate modernizing features such as: Tracking of Galileo Constellation (in addition to the current ones, GPS and GLONASS). Incorporation of additional frequencies (GPS L5 / L2C and Galileo E5a). Signal processing capabilities (such as integrated signal quality monitoring and in particular evil waveform detection using a multi-correlator architecture). Advanced built-in robustness and security functions: Robust tracking algorithms, detection/mitigation of interferences and antispoofing/jamming techniques. In this context, ESA awarded the consortium Indra and SPCOMNAV (a research group from the Universitat Autonoma de Barcelona – UAB) with a contract for the development of an advanced GNSS reference station breadboard (a.k.a. R3B) in the frame of the General Support Technology Program (GSTP 6.2) program. INTRODUCTION Indra has acquired during the last decades a large experience in the assessment of GNSS performances, not only at system level, but also at ground and user levels. This has been achieved thanks to the execution of several GNSS R&D projects and the participation in the development of different European GNSS programs, such as Galileo and EGNOS. This experience has led the company almost naturally to the compilation of previously developed and well-tested tools. The result of this compilation is the GNSS Performance Characterization Framework (GPCF). The GPCF has been customized to the particularities required by the R3B project. The original characterization framework is briefly introduced in this paper. The main focus of the paper is, however, the work performed throughout the R3B project using the GPCF. FRAMEWORK FOR PERFORMANCE CHARACTERIZATION GPCF is a toolset that allows analysis of GNSS data collected from different receiver types (mass market, differential, precision, etc.) and systems (SBAS, GBAS and GNSS). It can then be easily integrated within any test environment allowing the assessment of receiver and system performances such as: Position-Velocity-Time (PVT) solution accuracy and integrity. Code and carrier phase measurements accuracy, including estimation of effects such as inter-frequency biases, group delays, channel biases, noise errors, etc. Signal in Space acquisition and re-acquisition for GNSS and GEO satellites. Impact on the measurements and behavior of the receiver under a wide variety of complex scenarios including o Multipath errors of different nature (diffuse, reflective, etc.) o Interfering signals of different types (narrowband or wideband, pulsed or continuous, inter-system or intra-system, etc.) o Ionospheric Scintillation (IS) errors of different nature (high or low latitude IS) Orbit estimation accuracy. Code-carrier measurements coherence