The Indian Space Research Organisation (ISRO) recently demonstrated free-space quantum communication over a distance of 300 m for the first time.
The demonstration included live videoconferencing using quantum-key-encrypted signals. This is a major achievement for unconditionally secured satellite data communication using quantum technologies.
Isro said that a number of key technologies were developed indigenously to accomplish this major feat, which included the use of an indigenously developed navigation satellite system, with an operational name of NavIC, a receiver for time synchronisation between the transmitter and receiver modules, and gimbal mechanism systems instead of bulky large-aperture telescopes for optical alignment.
The Quantum Key Distribution