A new circuit structure for near field wireless power transmission

Wireless power transmission using mid-range magnetic resonance has become an important technology in body area sensor systems. Recent researches have used fine-tuned impedance matching for wireless power transmission at fixed distance. However, this method is significantly sensitive to the distance change between two devices since the impedances at both ends must be perfectly matched. Hence, it is a major challenge to achieve efficient wireless power transmission in mobile environment. We propose a new circuit architecture for wireless power transmission in the near field; the Resonator Isolation (RI) structure. Using the RI structure, the wireless power transmission becomes highly robust under mobile environment. In this paper, we present the circuit design of the RI structure and evaluate its performance with the actual systems we constructed.