Mechanical Antennas: Emerging Solution for Very-Low Frequency (VLF) Communication

This paper presents the concept of mechanical antennas for long range and under water communication systems and addresses its challenges and the corresponding solutions. In this approach, instead of using conventional antennas driven by a power source or oscillator, the radiation is mainly due to charge acceleration under mechanical forces provided in an engineered fashion. As illustrating examples, the radiation associated with rotating dipole charges and rotating magnets are theoretically derived and radiated power dependency on the frequency of rotation, dipole moment, required mechanical force and radius of rotation are investigated. The concept of magneto-dielectric resonance is finally utilized to enhance the radiated electric field from the mechanical antenna system by around 100 dB.