A new study shows the importance of adhering to FAIR principles when offering GNSS data and services.

By Ivana Ivánová et al

To effectively service current and future GNSS users’ demands in a robust way, geodetic data and their associated metadata — which are the main vehicle of any functional data or service subscription portal — need to be Findable, Accessible, Interoperable and Reusable (FAIR). At the same time, to support FAIR data reuse by both humans and machines, GNSS metadata also needs to be encoded in a machine-actionable way.

The FAIR guiding principles are reflected by the key characteristics of the data and services offered via data portals and subscription services. Through these, GNSS enable existing and emerging industries to use real-time precise positioning data, allowing them to improve productivity, efficiency and safety, while supporting a wide range of decision-making processes.

The range of current GNSS data users now extends significantly beyond the ‘traditional’ user segments. Traditional GNSS users, typically geodesists, geophysicists and surveyors, are trained to understand the specific jargon and data encoding used by data and subscription portals. ‘New’ users come from various application domains where GNSS receivers (many of which are low-cost and widely available) are increasingly used for many data collection, monitoring and navigation applications.

General requirements for the use of GNSS in various traditionally recognised application domains, such as surveying, agriculture, aerial (drone), road, rail or maritime operations, are readily available in most GNSS textbooks and research articles. However, it is unrealistic to expect that the wider GNSS community is aware of these.

Setting the standard

Standards play a crucial role when integrating GNSS and geodetic data with data from other domains in a FAIR manner. Current standards for geographic information that are relevant in the GNSS domain — such as the ISO 19100 series developed by the International Organisation for Standardisation and its Technical Committee for geographic information (ISO/TC211) or standards for geodata encoding and catalogue web services developed by the Open Geospatial Consortium (OGC) — support the FAIR principles reasonably well.

Although ISO and OGC standards are developed for generic ‘geographic information,’ many of them are relevant in the GNSS domain as well. To increase the FAIRness of GNSS data and services, the use of domain-specific standards in addition to generic standards is essential.

To date there has not been work done to investigate how both traditional and emerging GNSS user sectors understand and perceive the FAIRness of provided precise positioning data and metadata. It is essential that GNSS data and service providers understand users’ perspectives of FAIR, as this will help to reveal the potential challenges they face when interacting with these resources. As ISO and OGC standards are further developed with a strong producer-centric understanding, the needs of current and emerging GNSS users will inform the next editions of these fundamental documents.

Our new paper (doi.org/10.1162/dint_a_00185) summarises the perspectives of current precise positioning users regarding what constitutes data and metadata that comply with the FAIR principles. It also reviews support for FAIR in existing precise positioning and other related international standards, and investigates whether current standards have potential to address the expectations of GNSS users in various sectors.

Our results confirm that offering FAIR GNSS data and services is fundamental, but for a confident use of them, detailed and relevant metadata need to be offered to the GNSS community. We outline the approach towards fulfilling these expectations with standard-compliant GNSS community metadata profiles and providing relevant metadata with data on-demand through machine-actionable information models for FAIR GNSS data and services.

During our engagement with GNSS user sectors who operated across the GNSS value chain, we worked to understand user requirements, and to ensure that GNSS data and services that are compliant with the FAIR principles could be delivered to each sector. We propose the following improvements to current GNSS data and metadata delivery:

• Extending the metadata model currently in use to accommodate the metadata requirements of current GNSS data users;
• Defining a specific international standards’ compliant metadata profile for the GNSS community; and
• Ensuring metadata related to data and data streams are delivered with these.

Extended metadata encoded in or with GNSS data products will help users who subscribe to data services directly and help avoid the often-daunting browsing of metadata catalogues. This will be ensured by improved subscription services offering the best possible product as determined from comparison of expected quality requirements and metadata stored with the product, for an application identified by the subscriber.

This process is currently underway as part of follow-up work to the stakeholder engagement presented in the paper. We expect that this work and continued discussions within the geodetic community at IAG/IUGG and within the standardisation communities at ISO/TC211 and OGC, as well as ANZLIC’s ICSM, will be instrumental in defining the GNSS community standard, and thus in providing FAIR data and metadata to all GNSS users.

Authors: Ivana Ivánová (Spatial Sciences, School of Earth and Planetary Science, Curtin University), Ryan Keenan (Positioning Insights), Christopher Marshall (FrontierSI), Lori Mancell (Geoscience Australia), Eldar Rubinov (FrontierSI), Ryan Ruddick (Geoscience Australia), Nicholas Brown (Geoscience Australia), Graeme Kernich (FrontierSI).