A novel coaxial loop resonator for wireless power transfer

We present a novel resonator, based on a coaxial cable structure, suitable for wireless power transfer (WPT) applications. Its advantages are compactness, ease of manufacture, and low cost. WPT resonators generally operate in the HF, LF bands, using magnetic field coupling and a lumped capacitance for achieving the sought resonance. In our structure, the electric field is primarily confined inside the coaxial cable, whereas the magnetic field is generated by the currents flowing on the external conductors. The article describes the resonator structure, illustrates its design procedure, and discusses quality factor contributions. A few resonators with Q higher than 900, operating around 30 MHz, have been built, simulated, and measured confirming the validity of the proposed approach. (C) 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2012.