Status of the DLR OGSOP and its Development towards QKD OGS and multi-mission operation

Kurzfassung

The Institute of Communication and Navigation at the German Aerospace Center (DLR) hosts the Optical Ground Station Oberpfaffenhofen (OGSOP). The station is operating with an 80cm primary mirror telescope, including a Nasmyth configuration. These were guiding light to several different experimental ports at the Ground Station itself, as well as a free space optical Coudé-Path, leading onto an optical table inside the laboratory below the station. After the commissioning of the OGSOP (2021 – 2023) various projects and free space laser communication experiments have been conducted. OGSOP approved operations including data downlinks from the low orbit satellites Flying Laptop, CubeL and QUBE. Experiments with Alphasat (GEO stationary platform) were also carried out as well as an aircraft link campaign in the frame of QuNET project. The gained experiences and lessons learned of all these missions led to further development and upgrades of the OGSOP, especially from classical laser communication towards the direction of Quantum Key Distribution (QKD). The upgraded OGSOP and its peripheric systems are a designated test bed for QKD [1][2]. The QKD precursor Missions QUBE-I (launch August 2024) is already in the phase of an ongoing linking campaign at OGSOP. From first light to scientific experiments, the OGSOP could already proof its capability to support this type of optical free space satellite communication missions. The receiving Coudé-Path and system PUMUQL (Prototyping Unit for Modulated User-data and Quantum Links) was integrated for the quantum light, as well as an adaptive optics system in development. The follow up mission QUBE-II is also already launched (May 2026) and currently in its finally LEOP phase, it will will go into first tests around autumn 2026 at OGSOP. The preparation for Eagle-1 is a main part of the work and development for the optical ground station. QKD up- and downlink path is redesigned, implemented and brought into operational service. The growth of the number of projects dropping into the OGSOP was one of the reasons to go from classical project-based time by time mission support to a matrix like solution for multi mission support and operations. An established configuration management, new commanding, booking and preparation processes are assisting the whole organization. Following an overview of the current status of the OGS, the ongoing projects (QUBE, Eagle-1, QuNET, and more) will be given. A description of the ground stations infrastructure and support facilities will be represented in relation to different project requirements and missions.