Optical Communication Experiments at DLR

Abstract

In 2006 and 2009, the Institute of Communications and Navigation (IKN) of the German Aerospace Center (DLR) in a joined venture together with JAXA and NICT executed optical downlink experiments with JAXA’s OICETS/Kirari to investigate the optical LEO downlink channel and evaluate the feasibility of this transmission technology for future applications. The DLR Optical Ground Station at Oberpfaffenhofen near Munich comprised several devices for measuring the effect of the atmosphere’s index-of-refraction turbulence (IRT) and a data receiver frontend to quantify bit-error distributions. This project was named KIODO (KIrari Optical Downlinks to Oberpfaffenhofen). Results showed a strong dependency on link elevation for all IRTrelated parameters. These two successful measurement campaigns encouraged DLR-IKN to develop a laser test source for various small LEO missions to enable further investigations and optimizations of this technology for future telemetry data down- and up-links.