I. Introduction
Non-radiative wireless power transfer (NR-WPT) has emerged as a viable option to provide power and recharge batteries in biomedical implants [1]. There are some critical components of every NR-WPT system, such as the distance of power transfer and the size of the system. Furthermore, the requirement of a multi-band system stems from the fact that one frequency band can be used for data transmission and the other for transferring power to the implant. This paper makes use of semi-H shaped Defected Ground Structure (DGS) based resonator [5] and proposes a dual-band WPT system. DGS based resonators are simple to design and also provide a high Q factor to the system [2], [7]. Semi-H shaped design improves the inductance of the circuit, and this, in turn, enhances power transfer efficiency. This very idea has been exploited in this manuscript to improve the distance of power transferred and efficiency. First, a circuit model for the DGS band-stop filter (BSF) is proposed along with EM and circuit simulations. Then, the circuit model for the dual-band WPT system is deduced from the BSF. Subsequently, the validation of the proposed design is demonstrated using measurement results. Section V concludes this paper.