Optics InfoBase is the Optical Society's online library for flagship journals, partnered and copublished journals, and recent proceedings from OSA conferences.

In this paper, optical wireless has been addressed as a promising technology to provide high-bandwidth services for underwater communications. However, the significant attenuation degree due to high absorption and scattering of optical transmission in the water confines the achievable range of optical links to only few meters. One way to achieve transmission at long distances is to employ a dense network configuration where information can be transferred through a series of intermediate nodes acting as relays. In this study, we consider optical wireless network arrangements where nodes are floating at different depths into a service aquatic medium. We deploy an effective path loss model which incorporates the key factors that deteriorate the optical power, and we derive the achievable transmission range to satisfy connectivity criteria assuming intensity-modulation direct detection (IM/DD) with on-off keying (OOK). A set of numerical results is presented in order to reveal the interaction between various parameters such as error probability, wavelength, node density, transmitted power, data rate, etc., in order to achieve k-connectivity. The proposed analysis could be the basis of deploying reliable underwater optical networks suitable to deliver broadband services at far distances.

Visible light communication (VLC) is a promising technology that meets illumination and information transmission requirements in an indoor environment. Because light waves convey energy, a VLC link may exploit that fact for energy harvesting purposes. In this context, a single light emitting diode lamp located at a close distance over a tablet or laptop PC can potentially offer simultaneous lighting, Internet access, and battery recharging without cables. The present study introduces this threefold role of VLC systems by properly adapting some energy harvesting receiver architectures recently launched for usage in RF communications. The rate-energy trade-off for these architectures is revealed in order to maximize the efficiency of simultaneous energy and information reception, by elaborating on indicative numerical results. Furthermore, the performance in terms of the bit-error rate for pulse amplitude modulated signals is investigated. The results obtained offer some useful insights into the effective optical receiver implementation from the aspect of information theory.

Optics InfoBase is the Optical Society's online library for flagship journals, partnered and copublished journals, and recent proceedings from OSA conferences.

Achieving both illumination and data reception with probability almost one inside a specific indoor environment is not an effortless task in visible light communication (VLC) networks. Several factors such as error probability, transmitted power, dimming factor, or node failure affect coverage probability to a large extent. To assure reliable signal reception, a dense transmitting network is required on the ceiling. In this paper, we investigate how the key factors contribute to a network deployment with a reliable degree of coverage at a specific horizontal plane. Considering that VLC is set to be one of the most challenging technologies for domestic applications in 5G networks, the analysis on coverage issues discussed herein is of particular interest in practical scenarios.