The European Data Relay System (EDRS) is the most sophisticated laser communication network ever designed. Dubbed the ‘SpaceDataHighway’, EDRS will help Earth-observing satellites to transmit large quantities of potentially life-saving data down to Europe in near-real time. Its two geostationary satellites use optical links to gather low-orbiting satellites’ information at far higher data rates than traditional radio frequency beams.
Low Earth orbiting satellites must be in direct line-of-sight with their ground stations to pass on the information they’ve gathered while circling the Earth. This leaves an average of 10 minutes of downlink time for every 100 minute orbit. The data must be stored for the rest of the time. EDRS solves this problem by intercepting the LEO satellite’s data from its position in geostationary orbit, permanently holding its position over the EDRS ground stations and remaining in contact at all times
