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 207 of 350
communications towards collaborative entities if required. This function embeds the
physical media transportation between remote sites, e.g. using post mail services;
○ A FOS Communication Network (FCN) Function, responsible for all digital
communications between the PDGS and the Sentinel-2 FOS located at ESA/ESOC in
Darmstadt (Germany);
○ A Data Dissemination Network (DDN) Function, responsible for all communications
versus external PDGS data-product users. This function extends to the EDRS datadissemination
capability composed of TX and RX stations to respectively transmit and
receive the data via the EDRS dissemination transponder in broadcast;
○ A Voice Communication Network (VCN) Function, possibly reusing public telephone or
Voice-Over-IP (VOIP) services to enable human communications between PDGS
internal or external interfaces.
5.2.3 DATA MANAGEMENT FUNCTIONS
5.2.3.1 Data Reception (DRX) Function
5.2.3.1.1 Function Objectives and High-Level Description
The DRX function is responsible for data acquisition from the spacecrafts and front-end datahandling
activities.
As such, it is in charge of:
○ Data acquisition from the X-Band downlink interface of the Sentinel-2 spacecrafts
through a LEO tracking antenna, or in Ka-Band on a still antenna pointing to EDRS
spacecrafts relaying the Sentinel-2 data transmitted through the OCP;
○ Real-time demodulation of the acquired signal and front-end processing of the CCSDS
formatted bit-stream down to VCDU or ISP extraction;
○ Real-time local storage of the acquired data;
○ Real-time supply of the acquired ISPs or VCDUs to the DPC function as required for
the nominal Level-0 product generation;
○ On-request replay from local storage of the supply activities to the DPC function on
contingency or for simulation purposes;
○ Data housekeeping activities on the local-storage such as the autonomous cleaning of
old acquisition buffers after a configurable retention period (typically after 3 days);
○ Offering standard FTP/SFTP access on the local-storage for remote deposit or
download of pass data;
○ Systematic post-acquisition reporting on the data-reception quality to the MCC via the
DC according to the monitoring requirements of the MPA;
5.2.3.1.2 Design Drivers and Constraints
The following drivers and constraints are identified:
© 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.