Introduction -- Historical overview -- Electromagnetic modeling -- Design of ELF/VLF communications links -- Mechanical design -- Closed-loop transmitter control -- ELF/VLF receiver design -- Portable ELF/VLF radios.

This book describes a new, extremely low frequency (ELF)/ very low frequency (VLF) miniaturized transmitter concept, based on the mechanical motion of permanent magnets or electrets. The authors explain how utilizing the very high energy density of modern ferromagnetic and ferroelectric materials, such "electromechanical transmitters'' can provide much higher field generation efficiency than conventional antennas, thus enabling practical ELF/VLF wireless communications links. The text begins with the fundamental challenges of such links and provides an historical overview of the attempts that have been made to address these challenges. It then focuses on the design and implementation of practical electromechanical ELF/VLF transmitters, which is an interdisciplinary subject that spans multiple research areas including electromagnetics, power electronics, control systems, and mechanical design. The authors also describe how such transmitters can be combined with receivers and signal processing algorithms to realize complete ELF/VLF links in challenging environments. Provides the first comprehensive introduction to the rapidly growing field of electromechanical ELF/VLF transmitters; Explains the design, modeling, construction, and operation of electromechanical transmitters; Includes discussion of the use of electromechanical transmitters, within complete ELF/VLF radio links.