Wireless power transfer in-band communication system

Abstract

A transmitter module is used in a wireless charging system, and is used for performing in-band communication with a receiver module in the wireless charging system to provide a message to the receiver module. The transmitter module has a matching network, a rectifier and an impedance component. The matching network has at least one input terminal coupled to a coil of the transmitter module and at least one output terminal. The rectifier is coupled to the output terminal of the matching network. The impedance component is selectively coupled to the output terminal of the matching network to vary a reflected impedance of the transmitter module seen by the receiver module. By varying the reflected impedance of the transmitter module seen by the receiver module, the transmitter module communicates with the receiver module to provide power control commands, status and/or foreign object detection information.

Dependencies are inferred from the claim text.