Satellite-based quantum key distribution
Across the globe, innovative products and services are emerging based on advancing developments in quantum technologies. One of the most important is quantum key distribution (QKD), an application of quantum communication. The first commercial QKD products using fibre optic cables are already commercially available, however quantum communication via fibre optic lines is limited to a few hundred kilometres. By leveraging satellites for transmission, quantum key distribution can be made possible on a global scale.
DLR is designing new systems and developing key components for satellite-based quantum key distribution. One core component is the QKD terminal for CubeSats, which enables quantum states to be transmitted from low Earth orbit to the ground – with an extremely compact laser terminal design. The terminal is being used in two satellite missions – QUBE and QUBE2 – at different stages of development.
The special optical design supports two wavelength ranges at approximately 850 and 1,550 nanometres. A precision-controlled mirror ensures the necessary precise alignment of the transmission beam towards the receiving station. The quantum states are received on the ground using optical telescopes and the signals are captured by the telescope and transmitted to the QKD receiver, where the cryptographic key can be read.
Links:
German Aerospace Center (DLR)
Institute of Communications and Navigation
E-Mail contact-dlr@DLR.de
Credits: ©DLR
