Magneto-inductive (MI) communications

Many of the mine warfare (MM) operations performed in littoral environments face a common problem: the lack of a reliable wireless command, control and navigation channel. Coastal regions have numerous dynamic environmental factors like shallow bathymetry, acoustically reflective boundaries, wave and tide action, and marine growth that can render conventional acoustic communication and navigation systems ineffective. Alternate system technologies such as laser and seismic-based systems have been evaluated with limited success. The lack of a reliable wireless channel can prevent the coordination of multiple systems, increasing mission time requirements and risks to personnel while reducing overall effectiveness. New system concepts for future operational use in littoral environments require reliable wireless communication and navigation. To address the needs of the MIW missions, over the past several years Coastal Systems Station (CSS), with its industrial partner Magneto-Inductive Systems Limited (MISL), has developed and refined unique magneto-inductive (MI) communication, signaling and navigation concepts and hardware that use quasi-static AC magnetic fields as the channel. The physical properties of magnetic fields enable these systems to operate through any natural medium or medium boundary. The MI channel can provide seamless coverage of littoral MIW operations in shallow water, surf and beach zones. CSS/MISL have conducted a number of tests and evaluations of MI system hardware. The paper discusses MI technology and results to date, and concludes with proposed future efforts.