The objective of this project is to develop, install, and operate a prototype wireless acoustic communications system that will extend the reach of cabled seafloor observatory nodes to remote instruments and autonomous underwater vehicles. The wireless system leverages the cabled deep ocean nodes proposed for regional cabled observatories. The acoustic system adds significant value to the cabled observatory and reduces the cost of network access by allowing deployment of instruments in the area around a fixed node without the need to lay cable. The system is intended for AUV control and instruments with low to moderate data rates deployed for periods of up to a few years. In addition to modems on AUVs and instruments, the system consists of two major components, the acoustic receiver located near a sub-sea node that samples and streams raw acoustic signals through the fiber-optic cable to shore, and the receiver and control software that reside on generalpurpose workstations on land. The approach takes advantage of the high-speed network planned for new cabled observatories, and continued reductions in the cost of computing power. The raw acoustic data stream will be available on shore for tomography, marine mammal monitoring and other research. To ensure that the acoustic infrastructure developed for communications supports other science requirements, it will be developed with input from potential users. An initial version of the system will be fabricated and installed at the MARS observatory prototype.
