EDRS-C – Challenging Way of Bringing the Second Orbital Node into Space

Abstract

The European Data Relay System (EDRS), also known as the SpaceDataHighway, is designed to provide commercial data relay service to spacecraft in low earth orbit (LEO). It offers high data rates and short response times and uses optical and Ka-band links for two-way data transmissions. The project was established by the European Space Agency ESA in frame of the Advanced Research in Telecommunications Systems program (ARTES-7). ESA is also acting as an anchor customer contributing LEO missions from their Copernicus Program. The EDRS project was organized as a public private partnership (PPP) with the industrial prime contractor Airbus Defence and Space. Airbus owns, operates and provides commercial services for the SpaceDataHighway. With EDRS-A, the first orbital node of the system started routine operations in late 2016. It is a hosted payload on the Eutelsat 9B spacecraft and is operated by the German Space Operations Center (GSOC) in a mostly automated way. In a second step, EDRS-C, a complete satellite has been added. This time, GSOC is responsible for both, platform and payload operations. GSOC's work for EDRS-C was organized in two parts. The first part covered the preparation and execution of the LEOP as well as the in-orbit tests of platform and payload. The payload consists of 3 elements, the data relay equipment for EDRS, The HYLAS 3 Ka-band communication payload of Avanti, and ESA's Next Generation Radiation Monitor NGRM. The spacecraft is a 3-ton-class SmallGEO platform built by OHB Bremen, Germany, which was already operated by GSOC during the maiden flight, the Hispasat Advanced Generation 1 (HAG1) mission in 2017. For EDRS-C, the challenge was not only to perform another LEOP and IOT, but also to have the next project phase in view, the routine operations for platform and payload. The second part comprised the development and implementation of the ground segment for EDRS-C, and the execution of mission operations for the 15 years routine phase. It was initially planned to do this in parallel to the LEOP and IOT preparations, but after coordination with the customer, a step-by-step approach was agreed. This approach allowed concentrating on the LEOP and IOT tasks in order to gain a timely launch readiness. As a consequence, the routine phase related components and operational products had to be completed in parallel to the already ongoing IOT operations. This paper will give an overview of the EDRS-C mission and emphasize the challenges of the step-wise approach to prepare LEOP, IOT, and routine phase operation. It explains the integration of the new satellite with different technology into the existing SpaceDataHighway network, delivers an insight into the project management approach at GSOC for the different work tasks and contracts, and illustrates the harmonization of the EDRS-A and C payload operations. EDRS-C was launched in August 2019. The in-orbit test phase for platform and payload was completed successfully and the operational services could be started in 2020, so this paper can provide an up-to-date status of the mission. In addition, an outlook is given to adaptations and improvements of GSOC's ground segment components in preparation of further extension of the SpaceDataHighway fleet.