and OOK modulation [10]. Receiver sensitivities of \(-\)76 dBm, \(-\)74 dBm, and \(-\)70 dBm were achieved for 1 Mbps, 2 Mbps, and 5 Mbps data rates over a 10 m underwater channel, respectively, and a more than 100 m distance can be transmitted for a 2 Mbps data rate in pure seawater at 1 W transmitted power. For the underwater VLC system using OFDM modulation, [PERSON], [PERSON] et al. proposed a dual-branch, pre-distorted, enhanced, asymmetrically clipped, direct current biased, optical orthogonal frequency division multiplexing (PEADO-OFDM) scheme for underwater VLC systems [11]. The simulation results show that PEADO-OFDM can increase the spectral efficiency, enhance the tolerance against ISI, and improve the bit error rate (BER) performance. Furthermore, [PERSON], [PERSON] et al. proposed and experimentally demonstrated a simple sampling frequency offset (SFO) estimation and compensation scheme for OFDM-based underwater VLC systems [12]. The experimental results show that the proposed scheme can achieve a high estimation accuracy with low computational complexity. **VLC for other potential scenarios:** Besides, general indoor scenarios and underwater scenarios, VLC is also applicable to many other potential scenarios. Specifically, VLC can be used to realize high-accuracy positioning and navigation in indoor environments. [PERSON], [PERSON] et al. presented an indoor visible-light positioning (VLP) system based on red-green-blue (RGB) LEDs and a frequency division multiplexing (FDM) scheme, where the received signal strength (RSS) technique is adopted to estimate the receiver position for multi-cell networks [13]. Simulation results demonstrated an average positioning error of less than 2.2 cm for all chromatic points. Moreover, VLC can also be applied in vehicular communications by utilizing the headlamps or taillights of vehicles to transmit data. [PERSON], [PERSON] et al. investigated the performance of vehicular VLC employing mirror array-based intelligent reflecting surface (IRS) [14]. By optimizing the number of mirrors in the IRS, the energy efficiency (EE) can be successfully maximized. In addition, VLC can be integrated with other communication technologies to establish a hybrid system. Particularly, [PERSON], [PERSON] et al. proposed a hybrid millimeter-wave/VLC system and compared the propagation characteristics, including path loss, root mean square (RMS) delay spread (DS), K-factor, and cluster characteristics, between mmWave and VLC bands based on a measurement campaign and ray tracing simulation in a conference room [15], while [PERSON], [PERSON] et al. demonstrated a 294-Mb/s hybrid fiber/wireless link based on a single visible LED over a 1.5-m polymer optical fiber (POF) and 1.5-m free-space distance [16]. **The application of ML/AI in VLC:** Aiming to mitigate the adverse effect of nonlinearity in VLC systems, [PERSON], [PERSON] et al. proposed a predistortion approach using coefficient approximation without sampling the LED transfer function, and further utilized the bidirectional long short-term memory (BLSTM) approach to train the LED distortion correction without knowing the LED modeling at the transmitter side [17], while [PERSON], [PERSON] et al. proposed a pilot-assisted reservoir computing (PA-RC) nonlinear equalization algorithm for nonlinearity mitigation at the receiver side [18]. In addition to bandwidth limitation and nonlinearity, inter-symbol-interference (ISI) due to multipath reflection is another issue that needs to be addressed in high-speed VLC systems. [PERSON], [PERSON] et al. constructed a neural network (NN)-based transceiver to compensate for the varying ISI effect in VLC systems [19]. The application of multiple-input multiple-output (MIMO) transmission in VLC systems is a natural and efficient way to enhance the system capacity, and the combination of MIMO and index modulation can convey additional bits. To improve the BER performance of the OFDM-based generalized LED index modulation (GLIM) system, [PERSON], [PERSON] et al.