A system for wireless power transmission may include one or more charging panels and one or more powered devices. The charging panel may include a pilot analysis circuitry, processor and power transmitter. The pilot analysis circuitry may be configured to analyze the magnitude and phase of a pilot signal from the powered device, based on which the processor may be configured to determine a complex conjugate of the pilot signal. And the power transmitter may be configured to cause radiation of a focused wireless power beam to the powered device in accordance with the complex conjugate of the pilot signal and via one or more antenna elements. The charging panel may be one of a plurality of spatially-distributed charging panels each of which includes respective antenna elements that may form an array of antenna elements configured to collaboratively radiate wireless power as a distributed, retro-reflective beamformer.