New concept of an electromagnetic usage for contactless communication and power transmission in the ocean

We demonstrate a new concept of an electromagnetic usage in the sea. The concept is characterized by sharing one pair of transmitting and receiving antennas for contactless communication and power transmission. The antennas are designed as electromagnetic (EM) high-Q resonators and the lowest resonant frequency is used for power transfer. The higher frequency band is used for signal communications. Using this concept, the efficiency of power transfer can be relatively high and the high transmission rate can be possible. A s a test trial for verifying the above concept, a measurement system is set up and the power transfer and signal quality are evaluated. The results show the power efficiency can be over 40%, and the transmission rate can be 20 Mbps via sea-water of the 5 cm's thickness. The proposed concept can be used to realize a compact and maintenance-free wireless usage between different underwater systems, such as autonomous underwater vehicles (AUVs), remotely-operated vehicles (ROVs) and mother ships.