phase modulation (mCAP) is used to exploit the spectrum out of the 3-dB bandwidth of the LED, and a DSP-based solution is proposed to remove the baseline wander effect, due to flickering in the VLC system. Following two papers dealing with LED characterization, [PERSON] et al. [3], in his paper on \"_Experimental Characterization of RGB LED Transceiver in Low-Complexity LED-to-LED Link_\", proposes a low-complexity and energy-efficient LED-to-LED communication system, using off-the-shelf red-green-blue (RGB) LEDs, where the red sub-LED is employed as a photodetector in the photovoltaic mode, while the green sub-LED is the transmitter. Authors derive a formula for the LED photodetector response at varying distances, and propose a matched filter technique to increase the error-free distance of the system. [PERSON] et al. [4], in \"_Experimental Characterization of Single-Color Power LEDs Used as Photodetectors_\", analyze the spectral, temporal, and spatial characteristics of two single-color power LED series employed as the PD, as compared to a common Si PIN photodetector. The dual use of the same LED as an emitter and detector is discussed with respect to wavelength dependence and practical issues, with further filtering proposed. The next papers are devoted to modulation formats. [PERSON] et al. [5], in the paper on \"Optimized Analog Multi-Band Carrierless Amplitude and Phase Modulation for Visible Light Communication-Based Internet of Things Systems\", develop a VLC-based IoT system architecture based on mCAP modulation, with the emitter implemented in the digital domain, while the demodulation in the receiver is accomplished in the analog domain. The authors focus especially on the filtering aspects, and the usage of guard bands parameters is evaluated. In the paper on \"Advanced Modulation Format of Probabilistic Shaping Bit Loading for 450-nm GaN Laser Diode based Visible Light Communication\", [PERSON] et al. [6] focus on probabilistic shaping bit loading discrete multi-tone modulation, to improve the spectral efficiency and system performance. This is experimentally validated, through realization of a 10.23 Gbps laser diode-based transmitter, over a 1.2-m long transmission span, with a signal bandwidth of 1.5 GHz. The next three papers provide more insight into the simulations of specific channel parameters and unique systems. [PERSON] at al. [7], in the paper \"_Utilization of an OLED-Based VLC System in Office, Corridor, and Semi-Open Corridor Environments_\", focus on the unique organic LED panel transmitters placed on walls in various indoor environments, based on the 3D ray tracing simulations that the new statistics of root-mean-square delay the spread, from which optical path losses are derived. The next paper by [PERSON] et al. [8] on \"_A Loss Function for Training Neural Networks in Communication Systems_\" proposes a novel error vector magnitude (EVM) loss method, which seeks to reconnect the disparity between the evaluation performed when training a neural network and the evaluation of the overall communication system. The results experimentally validated the capabilities of the method, which consistently obtained the lowest EVM when deployed in a real experimental setup, using orthogonal frequency division multiplexing (OFDM) and spectrally efficient frequency division multiplexing with a varying bandwidth. [PERSON] et al. [9], in the paper on \"_A Comprehensive Open-Source Simulation Framework for LiFi Communication_\", provides an open source for fully functional access points equipped with the physical layer and medium access control, a mobility model for the user device, and integration between LiFi and WiFi, with handover capabilities. Optical camera communications (OCC) have been increasingly considered, both as a commercial product and as research, due to the availability of cameras in daily activity, through their implementation in mobile devices, industrial cameras, etc. This area is covered by the following six papers. [PERSON] et al.