Performance analysis of adaptive optics with a phase retrieval algorithm in orbital-angular-momentum-based oceanic...

Area of Science:

• Optical communication
• Wave phenomena
• Turbulence

Background:

• Orbital angular momentum (OAM) beams offer high-capacity links in underwater optical communication (UWOC).
• Oceanic turbulence (OT) severely distorts OAM beams, causing intermodal crosstalk and degrading UWOC performance.

Purpose of the Study:

• To propose and demonstrate an adaptive optics (AO) system utilizing phase retrieval algorithms (PRAs) for compensating OAM beam distortion caused by OT.

Main Methods:

• Simulated oceanic turbulence using the random phase screen method.
• Employed Gerchberg-Saxton algorithm (GSA) and hybrid input-output algorithm (HIOA) for phase-front reconstruction.
• Evaluated the effectiveness of AO correction on OAM beam distortion and bit error rate (BER) performance.

Main Results:

• The PRA-based AO approach effectively compensated for distorted OAM beams in simulated oceanic channels.
• Significant improvements in bit error rate (BER) performance were observed after AO correction.
• The hybrid input-output algorithm (HIOA) demonstrated superior convergence performance compared to the Gerchberg-Saxton algorithm (GSA).

Conclusions:

• The study validates the feasibility and effectiveness of PRA-based AO for correcting OAM beam distortions in UWOC systems.
• This research offers valuable insights for enhancing the robustness and capacity of underwater OAM communication systems.
• The findings pave the way for more reliable high-speed data transmission in challenging underwater environments.