Certain aspects of the present disclosure relate to methods and apparatus for detecting and powering a wireless receiver. An exemplary method generally includes scanning an area using a first plurality of ultrasonic pressure waves emitted from ultrasonic transducers on an ultrasonic phased array of ultrasonic transducers, detecting a first device in the area and determining a location of the first device in the area based on the scanning, and delivering a second plurality of ultrasonic pressure waves to the location of the first device in the area for powering the first device using the ultrasonic phased array of ultrasonic transducers.
