Long-Distance Wireless Power Transfer Based on Time Reversal Technique

Abstract

Wireless power transfer (WPT) using microwave irradiation can set human free from the annoying wires. However, WPT has low energy efficiency due to electromagnetic wave diffraction in the case of indoor non-line-of-sight (NLOS) and causes electromagnetic radiation pollution around the room in the case of indoor line-of-sight (LOS). Time reversal (TR) technique is an inverse operation of time-domain signals and makes full use of the multipath effect. TR technique can improve the efficiency and reduce the pollution due to its unique temporal – spatial focusing effect. We will detail the principles of TR with the finite TR arrays. What ’ s more, we propose a sequential convex programming (SCP) algorithm based on diode circuit to obtain the optimal frequency point amplitude to further improve energy efficiency. The simulation result shows that the TR-SCP-WPT system model will get the significant energy gain.