Closed-loop optomechanical gimbals maintaining optical beam alignment across 5,000 km orbital distances in presence of spacecraft micro-vibrations.
Reaction wheels and solar panel drive mechanisms introduce jitter at frequencies between 10 Hz and 1 kHz. Piezoelectric fast steering mirrors (FSM) operating in a 5 kHz control loop compensate for angular deviations down to 0.5 microradians, ensuring continuous single-photon coupling into single-mode fiber collimators.
With relative orbital velocities reaching 15 km/s, inter-satellite laser carriers experience optical Doppler shifts exceeding +/- 10 GHz at 1550 nm. Distributed feedback lasers dynamically lock their cavity resonance using electro-optic phase modulators synchronized to orbital ephemeris GPS data.