It could be very useful or nothing at all. Nobody knows. Not even Elon Musk.
On November 6, China has successfully launched a Long March 6 rocket along with which a payload of 13 satellites was sent to orbit. Among the satellites, a "6G Satellite" too was sent, as BBC describes. The problem with the payload is, the rest of the world is still several years back from finding out what "6G" really is.
5G is still in its infancy and is considered the fifth and most recent generation of wireless broadband networks. Real 5G networks run at frequencies ranging from 30 to 300 Gigahertz in millimeter waves, 10 to 100 times higher than previous 4G cellular networks. (However by claiming the upper end of the 4G range as 5G, some mobile phone companies cheat).
A global alliance known as 3GPP, which has yet to explicitly identify 6G, determines the definition of these cellular generations. Given the past of technology's never-ending march, it is likely that 5G will in the future be replaced by a new network. It's just not clear what 6G is going to be.
The satellite, known as Tianyan-5, was jointly built by China University of Electronic Science and Technology, Chengdu Guoxing Aerospace Technology, and Beijing Weina Xingkong Technology as a remote-sensing satellite. The satellite would test a high-frequency terahertz communication payload in addition to Earth observations, which could transmit data at speeds many times faster than 5G.
Cellular companies are looking at higher bandwidths for the next generation of cellular technology as cellular networks become increasingly congested, and the demand for faster speeds and lower latency continues to rise.
To reach data speeds greater than 100 Gbps, terahertz waves (THz), which are submillimeter waves sitting between microwave and infrared radiation on the electromagnetic spectrum, have been used. Unfortunately, the Achilles' Heel shares THz waves with the millimeter waves used in 5G. A strong absorber of terahertz radiation is water vapor in the Earth's atmosphere, reducing the spectrum of THz applications. The same problem continues to delay 5G's widespread growth, and if it uses THz waves, it will possibly impede the introduction of 6G.
Similar worries raised by the rollout of 5G could also be stoked by emerging technologies. The construction of 5G towers in towns caused rumors of conspiracy to flourish. People also wrongly connected the COVID-19 pandemic to 5G without any evidence, which could have inspired U.K. citizens. In recent months, almost 80 mobile phone towers have burned down.
Astronomers, meanwhile, threatened to sue SpaceX for jeopardizing the future of ground-based astronomy observations for its Starlink constellation of communication satellites. To stop light pollution from the lights of cities and radio waves from cell towers, observatories are already going to great lengths. The opportunity for blind observatories to look at those wavelengths of light is given by a blanket of communication satellites orbiting the earth.
Tianyan-5 launched an Earth-observing satellite from the Argentinean company Satellogic aboard a Chinese-built rocket. Satellites can provide high-resolution images covering 1.5 million square miles (4 square kilometers) a day in a sun-synchronous orbit at a sufficiently high resolution to discern individual trees in a forest. The satellite could help stop illegal logging and control crop catastrophes in forests. Time can say if the next "G" for mobile phones will be Tianyan-5.