# High-Speed Underwater Optical Wireless Communication with Advanced Signal Processing Methods Survey
## Abbreviations  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} Air & Air Free Space Channel \\ AMP & Amplifier \\ AODV & Ad Hoc on-Demand Distance Vector \\ APD & Avalanche Photodiode \\ APE & Analog Post-Equalizer \\ AUV & Autonomous Underwater Vehicle \\ BCE & Blind Channel Estimation \\ BDNet & Blind Detection Network \\ BER & Bit-Error-Rate \\ Bubble & Bubble Water Channel \\ CAP & Carrierless Amplitude and Phase \\ CCD & Charge-Coupled Device \\ Clear & Clear Ocean Channel \\ CNN & Convolutional Neural Network \\ Coastal & Coastal Water Channel \\ DAC & Digital-to-Analog Converter \\ DBMLP & Dual-Branch Multilayer Perceptron \\ DFE & Decision-Feedback Equalizer \\ DMT & Discrete Multi-Tone \\ DNN & Deep Neural Network \\ DSP & Digital Signal Processing \\ FDE & Frequency Domain Equalizer \\ FEC & Forward Error Correction \\ FFE & Feedforward Equalizer \\ FSO & Free-Space Optical \\ GaN & Gallium Nitride \\ GK & Gaussian Kernel-aided \\ Harbor & Harbor Water Channel \\ HG & Henyey-Greenstein \\ IoUT & Internet of Underwater Things \\ I-SC-FDM & Interleaved Single-Carrier Frequency Division Multiplexing \\ ISI & Inter-Symbol Interference \\ LD & Laser Diode \\ LE & Linear Equalizers \\ \end{tabular}  
\begin{tabular}{l l} LED & Light-Emitting Diode \\ LOS & Line-of-Sight \\ MAC & Medium Access Control \\ MARL & Multi-agent Reinforcement Learning \\ MC & Monte Carlo \\ MIMO & Multiple-Input Multiple-Output \\ ML & Machine Learning \\ MMSE & Minimum Mean Square Error \\ MPE & Memory Polynomial Model-Based Equalizer \\ MSE & Mean-Square Error \\ NLE & Nonlinear Equalizers \\ NLOS & Non-Line-of-Sight \\ NML & Non-Machine Learning \\ NP & Noise Prediction \\ NRZ & No Return to Zero \\ OAM-SK & Orbital Angular Momentum Shift Keying \\ OBS & Optical Base Station \\ OFDM & Orthogonal Frequency-Division Multiplexing \\ OOK & On-Off Keying \\ PAM & Pulse Amplitude Modulation \\ PAT & Pointing Acquisition and Tracking \\ PCVNN & Partitioned Equalizer Based on Complex-Valued Neural Network \\ PD & Photodiode \\ PIN PD & PIN Photodiode \\ PMT & Photo-Multiplier Tube \\ PPM & Pulse Position Modulation \\ QAM & Quadrature Amplitude Modulation \\ QDTR & Q-Learning-Based Delay Tolerant Routing \\ RF & Radio Frequency \\ RRC & Root Raised Cosine \\ SARSA & State-Action-Reward-State-Action \\ SiPM & Silicon Photo-Multipliers \\ SNR & Signal-to-Noise Ratio \\ SPAD & Single-Photon Avalanche Diode \\ SPF & Scattering Phase Function \\ STFT & Short Time Fourier Transformation \\ SWI & Sparse Weight-Initiated \\ Tap & Tap Water Channel \\ TE & Triangular Exploration \\ TFDNet & Time-Frequency Domains Deep Neural Network \\ TL & Two Transfer Learning \\ TPGE & Tunable Passive Gain Equalizer \\ TTHG & Two-term Henyey-Greenstein \\ Turbu & Turbulence Water Channel \\ Turbid & Turbid Water Channel \\ UAC & Underwater Acoustic Communication \\ UAV & Unmanned Aerial Vehicle \\ UM & Underwater Monitor \\ UOT & Underwater Optical Turbulence \\ UOWC & Underwater Optical Wireless Communication \\ UWC & Underwater Wireless Communication \\ VDFE & Volterra Series-Based Decision-Feedback Equalizer \\ VE & Volterra Series-Based Equalizer \\ ZF & Zero-Forcing \\ \end{tabular}