A New Compact Dual-Band Wireless Power Transfer System Using Interlaced Resonators

This letter presents a new compact dual-band wireless power transfer (DB-WPT) system. The proposed system is based on two individual transmitting (TX) and receiving (RX) structures. Each structure consists of two interlaced resonators to achieve compact size. A single microstrip line loaded by a surface mounted capacitor (SMD) is used for power feeding. Moreover, high miniaturization of the TX/RX structures is achieved by SMD capacitor loading. In the proposed DB-WPT system, power is transferred from/to the source/load through electromagnetic resonant coupling between the TX and the RX structures. An equivalent circuit of the proposed DB-WPT system is extracted, and then the optimized structures are fabricated and measured. The measured results are in good agreement with the simulated ones. The proposed DB-WPT system has a peak efficiency of 80% and 73% at a transmission distance of 17 mm for frequency 300 and 675 MHz, respectively.