This paper presents some theoretical and experimental analyses of the rotating-magnet based mechanical antenna (RMBMA), a promising portable transmitting antenna for ELF-ULF (3-3000 Hz) wireless communication. Based on the Amperian current model, a theoretical model is developed to analyze the electromagnetic fields generated by RMBMA. A prototype is manufactured and measured, and the measurements coincide well with the calculations based on the established theoretical model. The results reveal that this new technique can create a constant channel condition in complex propagation environment, and an RMBMA with a small size can produce an AC magnetic field of 1 pT at hundreds of meters across lossy media, such as soil and sea water.
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