The European Space Agency and the Institute of Optoelectronics at China\u2019s Academy of Sciences both claim they\u2019ve achieved gigabit links to satellites in geostationary orbit.<\/p>\n
The ESA went first with a February 26th announcement<\/a> of a successful experiment in which a terminal made by Airbus locked onto the Alphasat TDP 1 satellite, 36 000 km above Earth, and \u201cmaintained an error-free connection while transmitting data at 2.6 gigabits per second for several minutes.\u201d<\/p>\n \u201cEstablishing laser links between moving targets at this distance is technically very challenging. Continuous movements, platform vibrations and atmospheric disturbances require extreme precision,\u201d said Fran\u00e7ois Lombard, Head of Connected Intelligence at Airbus Defence and Space, in a canned quote. \u201cThis milestone is a further development of our long successful laser communication history; it opens the door to a new era of laser satellite communications to meet defence and commercial needs in the next decades.\u201d<\/p>\n China\u2019s Institute of Optoelectronics claimed its tech achieved a 1 Gbps link to a satellite 40,000km away.<\/p>\n In a pair<\/a> of announcements<\/a>, the Institute says it developed a 1.8-meter laser ground station that needed just four seconds to make a connection to an unnamed satellite and then held the link for three hours.<\/p>\n During that time, data flowed at a symmetrical 1 Gbps.<\/p>\n Machine translation of the Institute\u2019s announcements tells us the uplink \u201chinges on high-precision pointing closed-loop control, achieved through micro-radius-level dynamic tracking and real-time compensation using beacon light, ensuring the continuous and accurate projection of 1Gbps signal light onto the satellite.\u201d<\/p>\n The downlink sees integration of \u201ca high-order adaptive optics system and mode diversity coherent reception technology.\u201d The first of those techs corrects for signal distortion caused by atmospheric turbulence in real time, and the second \u201cintelligently synthesizes multiple signals to suppress fading, jointly ensuring clear, stable, and high-speed transmission of the downlink data stream.\u201d<\/p>\n The Institute is enthusiastic about the potential for its tests to enable upload of complex instructions to satellites in high orbit, turning them \u201cfrom \u2018data relay stations\u2019 to \u2018intelligent processing hubs,\u2019” and creating \u201cinfinite possibilities for us to reach a smart earth, a three-dimensional network, and even deeper space.\u201d<\/p>\n Maybe as scientists they\u2019re too polite to follow Airbus with mentions of potential military applications.<\/p>\n