Underwater Communication Employing High-Sensitive Magnetic Field Detectors

Magnetic communication is receiving significant interest in RF-challenging environments. Particularly in underwater environments and underground wireless sensor networks, magnetic communication is an emerging research area. In this paper, a new approach for magnetic underwater communication is presented and evaluated. In this approach, the receiver coil of a conventional magnetic induction communication system is replaced by a high-sensitive low-noise wideband magnetic field sensor. This concept enables a good detection sensitivity and, under certain conditions, an extended communication range. Most magnetic field sensors are small compared to equivalent search coils and offer a high bandwidth. Hence, they can be assembled in order to provide multiple-input multiple-output processing. Based on suitable channel modeling, trade-offs between system parameters are analyzed and the channel capacity is derived. Analytical results are supported by a prototype implementation. Potential application scenarios are studied, where emphasis is on mobile applications.