Miniaturized super low frequency transmitting antenna based on the three-phase induction motor

In this paper, a miniaturized super low frequency (SLF) transmitting antenna is proposed based on three-phase induction motor, in order to cope with the oversized antenna issue in low-frequency electromagnetic (EM) transmission.Equivalent time-varying low frequency electromagnetic fields can be generated by the working motor, which can be used as a transmitting antenna. For the sake of electromagnetic field analysis, rotating magnetic field inside the motor can be regarded as a model of rotating magnetic dipole. Firstly, this paper describes the relationship between the magnetic field of the motor and the rotating magnetic dipole, and the electromagnetic field distribution of the rotating magnetic dipole is obtained by Maxwell's equations. Secondly, its near field and far field characteristics are proved by electromagnetic simulation. Finally, the electromagnetic field distribution of the motor is verified through experiments. The results show that the three-phase induction motor has the radiation characteristics of the low frequency antenna.