Optical Satellite Links for telecommunications and time-transfer

Free-Space Optical Communications have gained increasing attention in the field of communication and navigation throughout the last years. After the first satellite downlinks, the technology has been further matured, leading to a large number of technology demonstrations showcasing various application scenarios. More recently emerging application scenarios in the satellite domain are the development of quantum communication systems for applications like quantum key distribution (QKD) and optical inter-satellite links for mega-constellations. The Optical Satellite Links department at the German Aerospace Center’s (DLR) Institute of Communications and Navigation has been researching these alternative communication systems for more than two decades. This research includes optical satellite downlinks for downlinking earth observation data, intersatellite-links supporting mega constellations, optical geostationary feeder links and optical time-transfers. This talk will give an overview about the work of the Optical Satellite Links department with contributions in the field of atmospheric impairments and their mitigation, optical communication terminals for data downlinks as well as inter-satellite links, systems for quantum key distribution (QKD) as well as time transfer and ranging. This paper will also give a brief overview about running as well as upcoming projects.