SpaceX’s Starlink is not the only project that uses space lasers to transmit data. The ability to transmit information at a speed of 100 Gbit/s over long distances using a satellite and a laser was demonstrated by the Chinese company Chang Guang Satellite Technology.
Image source: Chang Guang Satellite Technology
High-definition satellite photographs of the Earth’s surface were used as test images, and as an example, observation was carried out over the historical part of Beijing and the airport area in Doha, Qatar. The photographs were transmitted from a satellite using a laser beam to a ground-based vehicle. Unlike Starlink, the Chinese competitor uses a laser beam to transmit information not between spacecraft, but between satellites and ground-based receivers. Starlink, although it has conducted similar experiments, in practice uses radio waves to transmit information between satellites and ground objects.
According to representatives of Chang Guang Satellite Technology, the experiment demonstrates how laser transmitters can further expand the ability of Internet satellites to transmit information. As company representatives note, “this will play a key role in the transition from 5G NTN networks to the development of 6G satellite Internet infrastructure.” Chinese developers claim that they have found ways to ensure reliable communication with a satellite via a laser beam, even taking into account atmospheric phenomena such as clouds and precipitation. As noted, a Chinese company developing similar technologies for monitoring the earth’s surface is negotiating cooperation with Iran. Such technologies make it possible to transmit images at speeds of several tens of gigabits per second. Currently, Chang Guang Satellite Technology has an orbital constellation of 117 satellites; by 2027, their number is planned to increase to 300.