Equalization equal gain combining for a single-input to multiple-output underwater wireless optical communication...

Area of Science:

• Underwater wireless optical communication (UWOC)
• Optical physics
• Oceanic turbulence modeling

Background:

• Underwater wireless optical communication (UWOC) systems face challenges from oceanic turbulence.
• Single-input to multiple-output (SIMO) schemes are used to improve UWOC system reliability.
• Accurate modeling of oceanic water stratification is crucial for performance prediction.

Purpose of the Study:

• To evaluate the performance of a SIMO UWOC system.
• To propose and analyze an equalization equal gain combining (EEGC) algorithm.
• To derive analytical formulas for performance metrics in weak oceanic turbulence.

Main Methods:

• Developed an EEGC algorithm for SIMO UWOC systems.
• Derived closed analytical formulas for scintillation index and spatial coherence radius using the Yue spectrum.
• Obtained a closed-form formula for the upper bound average bit error rate (BER) for the EEGC SIMO system with ON-OFF keying (OOK) modulation.

Main Results:

• Simulations revealed performance underestimation/overestimation when oceanic stratification is treated as steady state.
• The proposed EEGC algorithm significantly improved SIMO system performance, especially with increased detector spacing.
• EEGC mitigated the impact of detector array layout compared to standard equal gain combining.

Conclusions:

• Dynamic oceanic water stratification significantly impacts UWOC system performance predictions.
• The EEGC algorithm offers a robust solution for enhancing UWOC system reliability and performance in turbulent waters.
• The EEGC algorithm demonstrates superior performance and adaptability to detector array configurations in UWOC systems.