High-resolution multi-static radar and distributed electronic countermeasures require sub-nanosecond clock alignment between aircraft flying kilometers apart. This research evaluates pulsed optical time-transfer over turbulent atmospheric channels.
By transmitting counter-propagating femtosecond laser pulses between two aircraft and calculating round-trip transit asymmetry, atmospheric refractive index fluctuations are cancelled in real time.
In-flight demonstrations between two business jets achieved a clock synchronization accuracy of 82 picoseconds across a 25 km separation baseline, surpassing traditional RF methods by three orders of magnitude.