The core technology of Xiaomi’s remote charging lies in space positioning and energy transmission. Xiaomi’s self-developed isolated charging pile has five phase interference antennas built in, which can accurately detect the location of the smartphone. A phase control array composed of 144 antennas transmits millimeter-wide waves directly to the phone through beamforming… More here.
The fact that this does not feel like a mere concept shows how far we have come. Thanks to Andrew.