Dotfast timing solutions are used on the International Space Station: https://uwaterloo.ca/physics-astronomy/news/photon-detector-module-gearing-international-space-station

The TDM-6G resolution was improved to 10 ps. 128 inputs, 6.2 Gcps, 10 ps. That’s not bad, is it?

When two pulses arrive in a small time intervall, the detector is not fully recovered when it receives the second photon. Therefore the second pulse