GSC Sentinel-2 PDGS OCD - Emits - ESA

ESA UNCLASSIFIED – For Official Use
GSC Sentinel-2 PDGS OCD
Issue 1 Revision 2 (draft) - 25.07.2010
GMES-GSEG-EOPG-TN-09-0008
page 71 of 350
Image Processing Parameters (GIPP) generated by the IQP out of its characterisation
and calibration activities.
○ The PDGS for the generation and delivery to CNES/CST of nominal Level-0 products
and preliminary Level-1 products as required by the above tasks.
In addition, the PDGS will act as physical interface between the IQP (at CNES/CST)
and the Sentinel-2 FOS (at ESA/ESOC) for the uplink of on-board configuration
parameter tables.
To support the above scenarios, CNES/CST is an integral part of the PDGS operation context
during Phase-E1 of each spacecraft.
4.2.6 CORE AND COLLABORATIVE PDGS
To provision for long-term evolutions of the GSC, optimise the exploitation of its resources,
and provide for flexibility in incorporating National contributions, the GSC operations concept
includes the notion of a core GSC complemented by “collaborative” elements.
The core GSC, centrally managed, aims at supplying the GMES core services as basis. In
complement, the collaborative part aims through National or third-party contributors at
improving the quality of the overall GSC services in performance (e.g. data-access
timeliness) or in the range of data-supply services provided (e.g. other products).
The PDGS operations concepts cover the core PDGS operations enabling the above
collaborations.
4.2.7 LOCAL STATIONS
The Sentinel-2 system requirements [RD-01] provision for the capability to downlink real-time
MSI acquired data directly from the Sentinel-2 spacecrafts X-Band interface to a network of
Local Ground Stations (LGS) owned, managed and operated outside of the GSC framework.
The Sentinel-2 satellite design accounts for such capability in its downlink budget and
commanding capability such that real-time Sentinel-2 data downlinks can be commanded
outside of the periods used for recovering via playback the memory recorded payload data to
a PDGS Core Ground Station (CGS).
Hence, the opportunities offered to LGSs for real-time data downlink will depend on the
operational CGS network, and will be constrained by the applicable data recovery scenario
and associated downlink budget constraints imposed by the spacecraft thermal and power
budgets.
In response, the Sentinel-2 PDGS will provide functionality to accommodate real-time
downlink opportunities within the above mentioned constraints while ensuring a consistent
data recovery scenario to the GSC Sentinels CGS network.
4.3 Operation Constraints and Drivers
This section reviews the major constraints having a direct impact on the PDGS operation
concepts. It comprehensively forms the main justification reference to the overall operation
concepts described in subsequent sections and chapters. Each constraining factor is briefly
© ESA
The copyright of this document is the property of ESA. It is supplied in confidence and shall not be reproduced, copied or
communicated to any third party without written permission from ESA.