In recent years, wireless communications have significantly evolved due to the advanced technology of smartphones, portable devices and the rapid growth of Internet of Things, e-Health, e-Commerce, intelligent transportation systems and social networking. Forecasted by the Cisco the wireless mobile traffic will be dominant over the data network by 2018 towards a new connected world in 2020 with also the upcoming 5G systems. More recently we have seen growing research activities in Optical Wireless Communications (OWC) as a complementary wireless communications technology to the more established radio frequency-based systems such as cellular, Wi-Fi and Bluetooth in order to overcome the spectrum crunch and provide high data rates in urban environment and crowded locations. The OWC technology offering advantages such as free license, wide bandwidth, inherent security and no radio frequency based interference, which makes it very attractive for the emerging 5G wireless communications. Nevertheless, the widespread deployment of optical wireless systems, namely infra-red, ultra-violet and visible light communications (VLC), will face a number of challenged including the weather effects (mostly outdoor), eye and skin safety regulations, compatibility with existing networks, mobility (mostly in outdoor environment), cost per device and volume, and device/system performance. This has led to a substantial volume of research activities both at academia and industry at a global level to address the challenges and make OWC system a more reliable and viable wireless option. This is supported by an exponentially growing number of publications, dedicated technical events, research funding and PhD studies.
The 4th workshop on Optical Wireless Communications will cover the entire field of OWC including the emerging VLC technology. In the last decade, we have seen a growing trend in research and development activities in the emerging field of OWC covering VLC and free space communications for indoor and outdoor application including underwater communications. For example, the EU COST action IC1101 on OWC the emerging technology, with over 22 member countries.