A magnetic resonant scanner comprising a receiving antenna, a detune circuit coupled to the receiving antenna and configured for switching the receiving antenna between a resonant mode and a non-resonant mode, the receiving antenna in the resonant mode configured for receiving a magnetic resonant signal of a magnetic resonant examination, the magnetic resonant scanner further comprising: an energy harvesting circuit electrically coupled in parallel with the detune circuit and configured for inducing a harvesting current flowing through the receiving antenna in the non-resonant mode and for harvesting electric energy from the receiving antenna, wherein the receiving antenna includes a first capacitor and the detune circuit is coupled in parallel with the first capacitor, wherein an input impedance of the energy harvesting circuit is adjustable to achieve a desirable level of the harvesting current, wherein the level of the induced harvesting current is determined by the input impedance Zin of the energy harvesting circuit, which is comparable to an open circuit, wherein the energy harvesting circuit is configured such that the harvesting current is decreased by increasing the input impedance of the energy harvesting circuit to improve an image quality of the magnetic resonant examination, and the harvesting current is increased by decreasing the input impedance of the energy harvesting circuit to increase the harvested electric energy, and wherein the desirable level of the harvesting current achieves a balance between the image quality and the harvested electric energy, and wherein the energy harvesting circuit further comprising: a rectifier having a rectifier impedance Zrec; and an impedance matching circuit configured for transferring the rectifier impedance Zrec to the input impedance Zin of the energy harvesting circuit. an energy harvesting circuit electrically coupled in parallel with the detune circuit and configured for inducing a harvesting current flowing through the receiving antenna in the non-resonant mode and for harvesting electric energy from the receiving antenna, wherein the receiving antenna includes a first capacitor and the detune circuit is coupled in parallel with the first capacitor, wherein an input impedance of the energy harvesting circuit is adjustable to achieve a desirable level of the harvesting current, wherein the level of the induced harvesting current is determined by the input impedance Zin of the energy harvesting circuit, which is comparable to an open circuit, wherein the energy harvesting circuit is configured such that the harvesting current is decreased by increasing the input impedance of the energy harvesting circuit to improve an image quality of the magnetic resonant examination, and the harvesting current is increased by decreasing the input impedance of the energy harvesting circuit to increase the harvested electric energy, and wherein the desirable level of the harvesting current achieves a balance between the image quality and the harvested electric energy, and wherein the energy harvesting circuit further comprising: a rectifier having a rectifier impedance Zrec; and an impedance matching circuit configured for transferring the rectifier impedance Zrec to the input impedance Zin of the energy harvesting circuit. a rectifier having a rectifier impedance Zrec; and an impedance matching circuit configured for transferring the rectifier impedance Zrec to the input impedance Zin of the energy harvesting circuit.