A Novel Dual Band Defected Ground Structure for Short Range Wireless Power Transfer Applications

A novel dual-band Wireless Power Transfer (WPT) for short range, non-radiative and inductively coupled design based on Defected Ground Structure (DGS) back to back coupling is presented in this paper. The proposed design is based around the concept of resonance inductive coupling for power transfer and consists of U-shaped defect etched in the ground plane of the substrate. An equivalent dual band circuit using transformer modelling is utilized to show power transfer at two frequencies. Prototypes on Rogers RO4003C substrate, has been developed to operate at 2.4 GHz and 5.8 GHz ISM frequency range and takes a board size of $15x1\theta \mathrm{mm}^{2}$. A very good agreement between the simulated and measured results demonstrate the effectiveness of the proposed technique. The achieved performance significantly improves the distance of the short range inductively coupled WPT systems reported so far.