Biblio

Magnetic induction (MI) has shown a great potential for underwater communications due to its immunity to acoustic noise and low latency. However, the transmission distance of MI is limited since the magnetic field attenuates very fast in the near field. In this work, a magneto inductive antenna design is studied to achieve two modes of operation: 1) a static quasi omni-directional magnetic coupling; 2) a dynamic rotation of magnetic coupling. A design procedure is described to define the strength of the magnetic field, bandwidth (BW) and the path loss (PL) of the underwater communication link. Both modes are simulated and the corresponding antenna configurations are described. The proposed antenna has three coils separated between each other by 120 degrees. The coils have a radius of 5 cm and a length of 8 cm. The simulation results illustrate how this design can provide an omni-directional magnetic coupling and a more directional performance in the rotation mode. In the rotation mode, simulations also confirmed that the magnetic field can be controllable by changing the phases of input currents.