Sentinel-2 POD - CPOD QWG

The Copernicus POD Quality Working Group (CPOD QWG) is a dedicated group of experts in Precise Orbit Determination who provide independent POD solutions, allowing to carry out external validation of the operational POD products. Additionally, they perform analysis to monitor the quality of the input tracking data, conduct research on improved models and algorithms and define potential and future enhancements to the orbit solutions. The members of the CPOD QWG meet usually twice a year to present the main findings since the previous meeting and to decide on which aspects are worth investigating in the near future.

The main tasks of the CPOD QWG can be summarised as follows:

  • Gather information: Through attending conferences and interactions with the IDS Analysis Working Group, the Copernicus POD QWG gathers information on any potential algorithm evolution that could benefit the Copernicus POD system. Besides, the interaction with the international services of all observation techniques available for the SENTINELs (IGS, IDS and ILRS) is maintained. The IERS conventions and realisations of the ITRF are updated. The evolution of the (CNES) GDR standards is also considered.
  • Evaluate: Evolutions are evaluated on a separate validation with at least other POD centre (CNES; ESOC). Quality indicators evaluated are orbit overlap, tracking data residuals, the magnitude of the empirical accelerations, external orbit comparison, and in the case of SENTINEL-3, altimeter crossover performance.
  • Make recommendations: The most promising enhancements are presented and discussed during the QWG meetings.
  • Implement changes: After the internal and external evaluation and approval of ESA the algorithm evolution is included in the next upgrade of the POD.
  • Membership: The composition of the Copernicus POD QWG is composed by representatives of ESA, EUMETSAT, CNES, NASA, GMV, POSITIM, DLR, TUM, AIUB, TU Delft, DGFI, GFZ, CLS, SENTINEL-3 Validation Team Meeting, the Mission Performance Centre of each SENTINEL, Payload Data Ground Segment of each mission, the Copernicus Service and the Post-Launch Support Office.

The main analysis presented and conclusions reached in each CPOD QWG meeting, held twice a year, are included in the S2 POD Document Library.