Optical communication for Underwater Wireless Sensor Networks: a VHDL-implementation of a Physical Layer 802.15.4 compatible

One of the challenging aspects in building an efficient underwater wireless sensor network (UWSN) is under-water wireless communication. Radio frequencies are strongly attenuated in water: the available radio modules such as Bluetooth or wireless LAN (IEEE 802.11), which operate in the gigahertz range, around 2.4 GHz, cannot be used underwater where, currently, acoustic communication is mainly employed. In the case of short-range distance, optical communication can be a feasible alternative solution, even if light is scattered and absorbed by water.