iDiver: Underwater Text Messaging and Locating System for Divers

Diver communication is vital for the US Navy while carrying out strategic underwater missions. Diver-to-diver communication and diver-to-vehicle communication can allow the sharing of information as it is discovered and also enable performing cooperative maneuvers. Emergency situations can also benefit from such communication. In addition to the communication capability, it would be useful to know the location of all the divers relative to the deployment vehicle during the mission. Such capability will allow operators on the deployment vehicle to guide the divers in their maneuvers and also provide immediate assistance during emergencies. Underwater acoustic communication presents unique challenges due to frequency selective fading, Doppler spread and multipath. A wearable underwater text messaging and location system (iDiver) based on multi carrier code division multi access (MC-CDMA) is proposed. The MC-CDMA protocol will help counteract intersymbol interference a key limitation in underwater acoustic communication. Location estimation will be performed using a combination of direction of arrival determination and inertial measurement units (IMUs). SCCI is collaborating with Prof. Stojanovic at Northeastern University, a leading expert in underwater communication. Phase I research will investigate the applicability of MC-CDMA to a network of divers. Phase II research will focus on hardware prototype development.