Model and Design of a Novel Low-Frequency Magnetic Signal Transmitter Based on Rotating Electret

The ultralow-frequency/very-low-frequency (ULF/VLF) band communication is stable and worldwide, which can penetrate into sea or underground with slight loss. It plays an irreplaceable role in oceanic great-depth communication, distant navigation, and geologic examination. In a conventional ULF/VLF transmission system, in order to effectively emit electromagnetic (EM) waves, the length of the trans...