The Chinese Academy of Sciences (Chinese Academy of Sciences, Cas) announced that the country is ready to launch a new generation of quantum communication satellites.
These satellites will be the next step after the successful launch of the world’s first satellite for quantum communication, Micius. The new satellites are designed to perform more complex tasks and will be deployed in low, medium, and high orbits. This will allow them to be used as platforms for experiments in the field of quantum science.
The distribution technology of quantum keys (QKD) involves the use of satellite-based photon sources that generate individual light quanta, known as cubes. These photons are polarized in specific orientations for the transmission of quantum information. The satellite is able to create random pairs of photons, forming secret keys that are transmitted to ground stations equipped with detectors to measure the polarization of incoming photons.
This method enables encrypted communication between two parties, with data being deciphered using keys created based on quantum properties. The Micius satellite achieved a milestone by setting a new record for secure data transfer using quantum funds. It successfully transmitted keys between ground stations in China and Austria.
The new quantum satellites will be placed in higher orbits, similar to those used by GPS satellites, providing a wider view of the Earth’s surface compared to the Micius satellite, which orbits at an altitude of about 500 km. The increased altitude will also result in longer visibility time for the ground stations.
Before signals can be sent from an altitude of about 10,000 km, the development of microvibration suppression technologies is crucial for the accurate transmission of optical or laser signals by the spacecraft. The timeframe for the new missions has not yet been announced.
CAS stated that quantum space technologies have the potential to contribute to breakthroughs in long-distance space exploration and the detection of gravitational waves in space.
China is not the only country actively working on changing methods of transmitting confidential data in space. Last year, Europe announced the development of the Eagle-1 demonstration satellite complex, which is a system for secure distribution of quantum keys. It aims to provide orbit verification and demonstrate the next generation of quantum key distribution technology throughout Europe.