VHDL modeling of PHY and MAC Layer modules for underwater optical wireless communication

In this paper the description of hardware modules for managing underwater wireless optical communication is proposed. The modules have been developed for testing purposes considering previous released protocols for optical wireless communication (i.e. IEEE 802.11-IR) and the characteristics of underwater medium and taking into account the possible integration with current technologies for terrestrial Wireless Sensor Network (WSNs). The here proposed work is a first step to pave the way for diffuse optical communication allowing to support optical communication in an Underwater Wireless Sensor Network (UWSN) of dense-deployed fixed nodes which could be used for different specific application, such as monitoring and surveillance, for shallow, coastal and inland water in the case of moderate/limited area. This paper describes in particular the design and the implementation of the PHY and MAC Layer described in an HDL language and implemented on Field Programmable Gate Array (a low cost, low power Actel IGLOO FPGA) along with a brief description of the circuits implemented to support the generation and reception of light impulse.