Through-the-Hull Data Transfer

Submarine outboard sensors must send data and receive power through a pressure hull consisting of two-inch thick HY-80, HY-100 or HY-130 high yield strength steel plate using hull penetrators that for safety reasons can only be installed during new construction or major refurbishments. As a result, hull penetrators are scarce resources and are difficult to acquire for temporary sensor installations.Electromagnetic and acoustic methods exist for sending data and power through many materials without penetrators. However, electromagnetic fields suffer high absorption loss in thick ferrous steel plate, making them a poor choice. Ultrasonic energy passes through high yield strength ferrous steel plate very efficiently and transfer of data at Mbps rates and power transfer of tens of Watts has been demonstrated.The submarine has unique requirements associated with the hostile outboard environment, the need to preserve stealth, and the need to avoid inducing corrosion of the pressure hull that prevent use of off-the-shelf solutions. A compact, low-power, high-performance ultrasonic modem pair that can transfer data from an outboard sensor at rates of Mbps or higher, and a separate modem pair that can provide ten Watts or more for powering the sensor and the outboard modems will be demonstrated.