Embodiments of the invention provide a magnetic resonant device. The magnetic resonant device comprises a receiving antenna, a detune circuit, and an energy harvesting circuit. The detune circuit is coupled to the receiving antenna for switching the receiving antenna between a resonant mode and a non-resonant mode. The receiving antenna in the resonant mode receives a magnetic resonant signal of a magnetic resonant examination. The energy harvesting circuit is coupled to the detune circuit for inducing a harvesting current flowing through the receiving antenna in the non-resonant mode to harvest electric power from the receiving antenna. Advantageously, with this simple and low cost power scheme, traditional cumbersome and expensive DC cablings can be eliminated from the magnetic resonant device.
