Analysis, Design and Optimization of a Combined wireless Power Transfer and Near Field Communication System

To achieve simultaneous data communication and wireless power transfer (WPT), this paper describes how Würth Elektronik has developed a combination of WPT and near field communication (NFC) coils in a single device. First, this paper describes the general setup of the WPT and NFC system. Constituent parts of the system are analyzed by simulation and verified by measurement. The design of the resonant tank for the wireless power components to achieve high efficiency is described. The optimal distances between the NFC-transmitter and €“receiver coils at different power levels are examined. The methodology for minimum reflectance and impedance matching of the NFC coil to the NFC IC is described. The interoperability of the WPT and the NFC coils is investigated. The trade-off in the separation of combination-transmitter and combination-receiver coils is considered. Finally, some typical applications and the advantages of the system compared to conventional NFC systems are discussed.