Expendable Acoustic Source for AUV Based Geoacoustic and Geotechnical Survey Operations

The EAS will be deployed by an LBS-UUV to conduct Naval Oceanographic Surveys in shallow water. The unit will consist of a housing containing a projector, a programmable power amplifier assembly, and a battery pack. The EAS projector will be designed to maximize the percentage of energy projected in the direction of the projector's face. The unit will sit with the projector face-down on the ocean bottom transmitting energy directly into the bottom sediment. This configuration will maximize the energy projected into the bottom sediment while minimizing the percentage of energy projected directly into the water column. This improves the effectiveness of characterizing the bottom sediment by increasing energy in the bottom while decreasing interference from water column based direct path transmissions from the projector to the receiver. Reducing energy in the water column also reduces environmental impact, and with the low levels being used (