Advanced atmospheric adaptive optics architectures for high-Rytov engagements

We present a unified adaptive optics (AO) wavefront control framework for three major atmospheric laser transceiver applications: (1) directed energy laser beam projection, (2) remote laser power beaming, and (3) free-space optical communications. We show that AO control based on the phase-conjugation (PC) concept naturally emerges from optimization of a generalized fidelity (error) metric, rather than from invoking the classical optical reciprocity principle prescribing conjugation of optical field complex amplitude (phase and intensity). The provided derivation of the ideal phase conjugation (IPC) control algorithm defines requirements for application-specific laser reference sources (laser beacons) for turbulence-induced aberration sensing and justifies the use of PC-type AO control algorithms in strong-scintillation conditions (high Rytov propagation regimes). The presented generalized IPC control concept assumes a hypothetical AO system with infinitely high spatial resolution in wavefront sensing and control. We also provide examples of more realistic advanced PC-type control systems utilizing a finite-resolution piston-type wavefront corrector, scintillation-resistant wavefront sensor, and application-specific laser reference source. The results of wave-optics numerical simulations demonstrated the potential efficiency of the proposed control system architectures in strong scintillation conditions for the atmospheric laser transceiver applications.