Surface Electromagnetic Waves at Seawater-Air and Seawater-Seafloor Interfaces

Underwater radio communication using surface electromagnetic waves propagating along the seawater-air and seawater-sea floor interfaces may provide a promising alternative to commonly used acoustic communication underwater. Here we present a detailed analytical and numerical consideration of TE and TM polarized surface electromagnetic wave properties. The resulting surface waves have propagation constants that permit communication ranges far longer than those of bulk propagation in the lossy media. We demonstrate theoretically and experimentally their ability to carry broadband radio signals over practical communication distances underwater. A 50 MHz radio signal was successfully carried along the sandy seabed over 7 m distance.