ACOUSTIC-OPTICAL MODEL FOR COMMUNICATION IN OCEAN WATER

Abstract

In recent years, Chinese Military activities have significantly increased underwater (specifically in Indian Ocean) which is a cause of concern for our security at sea. There is an urgent need to develop highly reliable, Low power consuming and small in size (size of equipment including transmission and reception antenna) Underwater wire-less data exchange (UWC) systems in Ocean Water. The initial purpose is to improve a personal understanding of both the current and vintage Underwater wire-less data exchanges methods used in modern systems. A series of experiments using Arduino Uno (physical experiments) and using MATLAB (virtual environment) were conducted for comparison between Acoustic and Optical transmission. This was the foundation for progressing to Acoustic-optical systems which is highly promising in terms of reliability and power consumption if favorable results are obtained. It is pertinent to mention that as on date wholesome wireless communication systems are not deployed or in use for Underwater wire-less data exchange in Indian Navy. All systems depend on raising an antenna from the diver to the surface of water and from there the reception happens. Even for diving a cable is laid for communication between diver and ship. Since the diver has power and size constraints focus is only on simplex transmission (one directional) from ship to diver. This work deals with the identification of most reliable Segment for Underwater wire-less data exchange in ocean environment between surface vessel and diver carrying out diving operations in saline water medium. Identifying a reliable and truly wireless method for Duplex data communication from Ship to Diver which is a Fusion duplex photosensitive-auditory design comprising of (i) downlink for the divers is a widespread-angle which will be omnidirectional and lower- bandwidth acoustic channel link and (ii) uplinks will be greater-bandwidth to carry video feed from diver to ship, highly directional optical links concentrated in one particular direction to feed the video to the ship so that correct instructions can be relayed to diver for various operational tasks like salvage, demolition, underwater welding, cleaning of equipment. The simulations of the acoustic and optical model in ocean water have been done using MATLAB, Simulink and LABVIEW.