Design of Algorithm for Multicarrier Modulation to Improve Transmission Performance of Inductive Coupling Temperature–Salinity–Depth Chain

Abstract

The inductive coupling temperature–salinity–depth chain uses seawater as a medium, where the transmission of electrical signals has multipath effect in infinite seawater. When the transmission frequency is increased, multipath delay spreads, inter code crosstalk, and selective fading of the received signals will be enhanced. In this letter, the finite-element simulation and numerical calculation are used to determine the key parameters, such as the number of paths, time delay, and channel attenuation factor. A multipath mathematical model of a long-distance inductively coupled channel based on electric current communication is established. Finally, an algorithm for multicarrier modulation, suitable for the channel, is proposed. The simulation results show that the proposed algorithm for multicarrier modulation can effectively resist multipath fading and improve system transmission performance.