Jinan-1 quantum satellite establishes first QKD between hemispheres (Beijing to South Africa, 12,900 km)

University of Science and Technology of China (USTC)/Jinan-1 Quantum Microsatellite and QKD

Pan Jianwei's team at USTC and collaborators at Stellenbosch University demonstrated real-time quantum key distribution via the Jinan-1 microsatellite across 12,900 km between Beijing and South Africa. The 95.9 kg satellite, 45 times cheaper and 10 times lighter than its Micius predecessor, transmitted quantum photons at 850 nm using decoy-state BB84 to establish encryption keys in real time during satellite passes.

• Jinan-1 transmits 850 nm quantum photons to portable ground stations (100 kg vs 13 tonnes for earlier systems).
• Secure key generation ranged from 406,784 to 1,071,104 bits per satellite pass depending on atmospheric conditions.
• Demonstrated real-time key distillation during passes, not after days of processing.
• Satellite decayed April 19, 2025; research lays groundwork for next-generation constellation planned by 2027.