PROARAIM: Towards the Early Adoption of ARAIM Air Navigation Services

The Advanced Receiver Autonomous Integrity Monitor (ARAIM) concept is being developed as an evolution of the previous RAIM technology. The Receiver Autonomous Integrity Monitoring (RAIM) technique has been widely used in aviation GNSS receivers as an ABAS augmentation to GNSS core constellations. Nowadays it is based in GPS L1 and protects from single satellite faults. The ARAIM concept takes advantage of the GNSS modernisation programs, using the new constellations and signals available for civil aviation navigation. ARAIM includes the capability to detect and exclude multiple satellite faults up to constellation faults, based on the constellation characteristics received via an Integrity Support Message (ISM). The initial ARAIM service will support a Horizontal ARAIM solution (H-ARAIM), and is expected to highly improve horizontal navigation availability, providing superior performance compared to traditional RAIM. ARAIM services will increase the alternatives available for an ANSP to choose the most suitable navigation means to develop an airspace efficient and safe for use. The advent of new GNSS services in support to flight operations requires introducing new technologies and procedures that will permit the continuous monitoring of their compliance with the accuracy, integrity, continuity and availability performance requirements specified in SARPs. Besides, availability predictions are also required to improve the continuity performance of a GNSS service. In this context, the PROARAIM project aims to ease the early adoption of ARAIM services through the pre-development and experimentation of some of the key elements needed to validate and approve future ARAIM flight operations, with the here called ARAIM tool suite. The PROARAIM project is co-founded by ESA as part of the NAVISP program and carried out by ENAIRE, the Spanish Aviation Navigation Service Provider; and GMV, one of the key players in Europe in GNSS augmentation infrastructure and services. This paper presents the PROARAIM project initial results and pending activities.