Apple Inc.
Electronic devices with wireless charging antenna arrays

Abstract:

An electronic device may transfer power wirelessly to an external device. The electronic device may include a housing having a cavity. A cover layer may be formed over the cavity. An array of antennas may be formed within the cavity. Antennas in the array may transfer wireless charging signals to the external device through the cover layer to charge the external device while the external device is in contact with the cover layer. Impedance detection circuitry may gather impedance matching information from each antenna in the array. Control circuitry may select an antenna having a best impedance match with the external device for transmitting the wireless charging signals. One or more antennas in the array may form a block filter for the selected antenna. Multiple near-field coupled antennas in the array may be selected for transmitting the charging signals to focus the charging signals on the external device.