A near field communication system for wireless charging

Resonant induction wireless charging requires two-way communications between the ground side and the vehicle side charging apparatus for vehicle identification, billing, charge control and for other communications and control requirements. To date vehicle wireless charging systems have used off-the-self digital communications devices operating half-duplex operating in the very popular but increasingly crowded 2.45 GHz ISM band. While readily available, and easy to use, such systems are not well suited for wireless charging communications and control for a number of reasons including the difficulty of single node, non-network operation, susceptibility to multipath, obstructed microwave propagation paths, increasing interference, non-propagation through standing water, wet snow or wet leaves, lack of physical layer security and perhaps most critical lengthy and variable communications latency. This paper introduces a novel full duplex, near field communications system designed specifically for wireless vehicle charging communications and control that employs magnetic induction as opposed to free space propagation as the communications medium combined with a unique coherent transponder topology that insures single node specificity while providing a notable measure of physical layer security. This proposed communications system is designed for simple international regulatory approval and can be inexpensively implemented as a single digital or analog application specific integrated circuit.