A Compact Readout Electronics for the Ground Station of a Quantum Communication Satellite

Free-space quantum key distribution (QKD) is being developed for achieving unconditional secure communication over ultra-long distance, which requires higher electronics performance, such as higher time measurement precision, higher data-transfer rate, and higher system integration density. As part of the ground station of the Quantum Science Satellite that will be launched in 2016, we specifically designed a compact PCI-based measurement and control electronics with high time-resolution and high data-transfer-rate. Some necessary modules in the quantum communication experiment such as multi-channel counter, system monitor and experiment control are also integrated in a single board. The electronics performance of this system was tested, with the time precision bin size is 23.9 ps and the time resolution root-mean-square (RMS) is less than 24 ps for 16 channels. The dead time is 30 ns. The data transfer rate to a local computer is up to 35 MBps, and the count rate is up to 30 MHz. The system has been proven to perform well and operate stably through a test of in-door free space QKD experiment.