A Comprehensive Analysis, Design, and Experimental Evaluation of Single-Loop Polygonal Slotted RF Resonators and WPT Systems

A thorough analysis of slotted ground plane (SGP)-based resonators designed for wireless power transfer (WPT) applications is reported in this paper. For the first time, some new findings that relate a resonator and WPT performance metrics to the slot shape, quality factor (Q), and radiation loss are presented in a very comprehensive manner. As a case study, a single-loop polygonal shape was considered to carry out all analyses and investigations. It has been identified that the slot shape has no impact on the performance of resonators and, hence, developed WPT. Instead, the performance is hugely dependent on Q of resonators regulated by the chosen slot area. These findings allow the conceptualization of systematic analysis of WPT systems and the development of design schemes that are readily realizable, and they also enable significant improvement in power transfer efficiency (PTE). The developed prototypes conforming to the industrial, scientific, and medical frequency bands show an enhancement in PTE to the extent of 11% during the measurements. The proposed analysis and design approach are very important steps in advancing state-of-the-art radio-frequency WPTs. In essence, this has the potential to reinvigorate the stagnated SGP-based WPT systems so as to facilitate the requirements of low-power applications.