Phase Corrections With Adaptive Optics and Gerchberg-Saxton Iteration: A Comparison

Free space optical communications technique is the promising alternative for the access/fronthual networks to relieve the traffic congestion. The turbulence in the free space channel, however, could cause the phase distortions in optical signals, thus degrading the performance strikingly. The air turbulence effect poses a challenge for such networks deployment. To this regard, we study the phase corrections with the adaptive optics (AO) and Gerchberg-Saxton (GS) iteration to mitigate the air turbulence effect under various turbulence conditions. The improvement in performance is comprehensively compared between the both schemes. The numerical results reveal that both AO system and GS iteration enable to effectively compensate for the phase distortions resulting from the air turbulence. Under weak turbulence, the GS iteration may outperform the AO in phase correction. On the other side, as the air turbulence is into strong regime, the AO would be superior to the GS iteration.