Time Reversed Electromagnetic Wave Propagation as a Novel Method of Wireless Power Transfer

Thumbnail Image
Publication or External Link
Cangialosi, Frank
Challa, Anu
Furman, Tim
Grover, Tyler
Healey, Patrick
Philip, Ben
Roman, Scott
Simon, Andrew
Tabatabai, Alex
Tao, Liangcheng
Anlage, Steven
We investigate the application of time-reversed electromagnetic wave propagation to transmit energy in a wireless power transmission system. “Time reversal” is a signal focusing method that exploits the time reversal invariance of the lossless wave equation to direct signals onto a single point inside a complex scattering environment. In this work, we explore the properties of time reversed microwave pulses in a low-loss ray-chaotic chamber. We measure the spatial profile of the collapsing wavefront around the target antenna, and demonstrate that time reversal can be used to transfer energy to a receiver in motion. We demonstrate how nonlinear elements can be controlled to selectively focus on one target out of a group. Finally, we discuss the design of a rectenna for use in a time reversal system. We explore the implication of these results, and how they may be applied in future technologies.