Chinese Researchers Develop Portable Ground Station for Quantum Satellite Communication

Chinese scientists have developed a quantum satellite ground station that is not only capable of sending ultra-secure messages anywhere in the world but can also fit inside a small car. The mobile device, developed by the University of Science and Technology of China, weighs about 80 kg (176lbs). With the addition of a 28 cm (11 inch) telescope, it can connect to the Chinese Academy of Sciences’ quantum satellite known as Mozi, and receive ­encryption keys in the form of ­entangled light particles.

Unlike traditional encryption methods based on Mathematics, quantum encryption is protected by the fundamental law of Physics. In theory, all information scrambled by encryption algorithms can be cracked by a computer if it is fast enough, but quantum key communication will remain intact because any attempt to eavesdrop will cause a physical change in the message and trigger a security alert to the sender or receiver.

The project team and collaborators from the Jinan Academy of Quantum Technology tested the device on a rooftop in Jinan, Shandong province. It established a near-perfect line of light with Mozi using laser beams and, in eight minutes, received quantum keys sufficient for the encryption of a large amount of data for long-distance transmission.

Shi Yipeng, a professor of Physics at Peking University, stated that the mini ground station will play a critical role in the application of quantum communication technology in scenarios that previously existed only in our imaginations. 

Concerns about information privacy are growing. The Prism project exposed by former National Security Agency contractor Edward Snowden, for instance, allowed the US government to tap into phone calls around the world that were supposedly scrambled. The situation started to change when China launched the world’s first quantum satellite in the year 2016. Named after the ancient Chinese philosopher and scientist Mozi, the satellite-enabled Chinese and European scientists to make video calls that could not be infiltrated by Prism or other digital espionage programs.

But the equipment that was used to receive the signals from the quantum satellite was bulky. China, for instance, built five ground stations to house the hardware that had a combined weight of more than 10 tonnes. They also required telescopes with diameters exceeding a metre to establish and maintain contact with the satellite.

Shi also stated, ‘Worst of all, it pinned the recipient to one location. In real life, many potential users are on a moving platform. Although the new portable station opened the gateway to quantum satellite communication for homes and businesses, it would most likely to be the first used by the military and will fit in a plane or submarine.’

The global competition on quantum technology is heating up, especially between China and the US. The consensus in the research community is that while the US is a step ahead in the field of quantum computing, China has the lead on quantum communication.

Strider, a security company based in Washington, whose board members include a former senior counterintelligence official with the FBI, has accused Chinese quantum researchers of working with the Chinese military and suggested that they are banned from working with the US scientists. Meanwhile, the US Air Force is funding research by civilian institutes, including Stanford University, into long-distance quantum communication technology, according to the university’s website.

The US Army funded a similar project with the University of Innsbruck to develop quantum internet for “military security, sensing, and timekeeping capabilities not possible with traditional networking approaches”, according to a statement by the US Army Research Laboratory in September last year.