Loop antennas with selectively-activated feeds to control propagation patterns of wireless power signals

摘要

An example wireless power transmitter includes: (i) a ground plate, (ii) a conductive wire offset from the ground plate, the conductive wire forming a loop antenna that is configured to radiate an RF signal for wirelessly powering a receiver device, (iii) a plurality of feed elements extending from the ground plate to the conductive wire, each feed element being connected to the conductive wire at a different position on the conductive wire, and (iv) a power amplifier connected to one or more feed elements of the plurality of feed elements. The power amplifier is configured to selectively feed the RF signal to a respective feed element of the one or more feed elements based on a location of the receiver device relative to the plurality of feed elements.