China and the U.S. are in a race to establish the first laser-based satellite communications network, which could greatly increase the speed of communications between the Earth’s surface and satellites in orbit.
As the South China Morning Post reported Wednesday, China recently conducted a test of the laser-based communications system, which could allow satellites to beam several gigabytes of data per second to Earth’s surface, rather than the rather than smaller kilobytes per second of information they can currently handle.
China tested the laser-communications system between satellites in its GPS-equivalent BeiDou satellite navigation system and ground stations on Earth. The South China Morning Post did not specify when exactly China’s laser communications test took place but reported the Chinese Academy of Sciences announced on Friday that the test proved BeiDou’s laser signals could transmit information effectively, even to challenging environments like crowded cities.
China’s test comes days before NASA is set to test America’s own laser-based satellite communications system. On Tuesday, NASA announced it will provide live coverage of its Laser Communications Relay Demonstration (LCRD) on Sunday, Dec. 5. The test will see if the system can transmit space-to-ground laser communications and link ground stations in Hawaii and California. NASA’s test is aiming to transfer 2.8 gigabytes of information per second.
NASA’s LCRD test comes after more than four years of delays. In May of 2018, the U.S. General Accounting Office (GAO) assessed that delays, funding cuts, and cost overruns would mean the LCRD launch would be pushed back to some time in November of 2019, “23 months later than the preliminary cost estimate.” In June of 2020, Parabolic Arc reported the intended launch date had again slipped from November of 2019 to January of 2021.
China and the U.S. may be just beginning to tap into the potential for lasers to effectively transfer large sums of information. The South China Morning Post reported such laser communications systems may be able to transmit up to one terabyte (1,000GB) per second.
In addition to being able to transfer larger amounts of data than past systems, laser communication systems make it harder for communications to be intercepted by hackers or jammed by electronic warfare means.
Satellite positioning systems like GPS and BeiDou are not only used to provide civilian navigation assistance but also for military means, such as identifying precise locations of units on the battlefield and accurately guiding weapons to their intended targets.
Protecting satellites against jamming and hacking could take on new significance. Last week, U.S. Space Force Gen. David Thompson said China and Russia are targeting U.S. satellites with electronic attacks “every single day.” The attacks have used means like laser dazzlers, radiofrequency jammers and cyberattacks to disrupt U.S. satellite operations.
China’s BeiDou system already has some advantages over GPS. In June of 2020, Reuters reported that when complete, BeiDou will be accurate down to 10 cm in the Asia-Pacific region, compared with a 30-cm range with GPS.
Andrew Dempster, director of the Australian Centre for Space Engineering Research, told Reuters, “Beidou was obviously designed a few decades after GPS, so it has had the benefit of learning from the GPS experience. It has some signals that have higher bandwidth, giving better accuracy. It has fewer orbit planes for the satellites, making constellation maintenance easier.”
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