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Wavefront of light passing through turbulent atmosphere gets distorted. Thiscauses signal loss in free-space optical communication as the light beamspreads and wanders at the receiving end. Frequency and/or time divisionmultiplexing adaptive optics (AO) techniques have been used to conjugate thiskind of wavefront distortion. However, if the signal beam moves relative to theatmosphere, the AO system performance degrades due to high temporalanisoplanatism. Here we solve this problem by adding a pioneer beacon that isspatially separated from the signal beam with time delay between spatiallyseparated pulses. More importantly, our protocol works irrespective of thesignal beam intensity and hence is also applicable to secret quantumcommunication. In particular, using semi-empirical atmospheric turbulencecalculation, we show that for low earth orbit satellite-to-ground decoy statequantum key distribution with the satellite at zenith angle $< 30^\circ$, ourmethod increases the key rate by at least $215\%$ and $40\%$ for satellitealtitude $400$~km and $800$~km, respectively. Finally, we propose amodification of existing wavelength division multiplexing systems as aneffective alternative solution to this problem.

Reducing The Impact Of Adaptive Optics Lag On Optical And Quantum Communications Rates From Rapidly Moving Sources