Magnetic induction to cross the air-water interface

Abstract

The use of magnetic induction is investigated. to cross the air-water boundary., A detailed derivation of the magnetic induction between two coils is introduced: one underwater and the other, above the surface. This new model is compared to a simpler model given by Wait. A circuit analysis is performed on both a transmitter coil underwater and a receiver coil in the air. The ratio of the induced voltage of the receiver over transmitter current as a function of frequency is analyzed in order to find the optimal frequency at a given coil separation. The addition of a passive repeater between the coils is also investigated to determine if it improves performance. A coil antenna system is designed in order to perform air and air-water tests to verify the model.