The portal is the public front-end of the “EPOS-GNSS Data Quality Monitoring Service” (DQMS) maintained by the Royal Observatory of Belgium.
The DQMS monitors the availability and quality of the daily GNSS data that are made discoverable through the TCS “GNSS data and products” (EPOS-GNSS) via the EPOS-GNSS data nodes and the EPOS-GNSS Data Gateway (DGW).

Who should use it

• Station operators: If you run a GNSS station that contributes data to EPOS-GNSS, this portal lets you check whether your daily data are being populated properly at the nodes (availability) and whether the data quality meets expectations.
• Node managers / DGW administrators: Those responsible for EPOS-GNSS data nodes can monitor the performance of all stations as well as the node infrastructures itself and detect issues early.
• Researchers / data users: If you use GNSS data from EPOS to produce geophysical products (e.g., station velocities, deformation maps), the portal helps you assess the data quality and reliability of the underlying observations before interpreting results.

Why it matters

• GNSS data quality is critical: Poor data (missing observations, high cycle slips, multipath problems) can lead to biased geodetic or geophysical results (e.g., misleading station displacement).
• It fosters operational oversight of a distributed European GNSS infrastructure: many nodes, many stations — monitoring helps maintain and improve network performance.
• The portal supports FAIR-data principles (Findable, Accessible, Interoperable, Re-usable) by ensuring data quality is transparent and monitored.