Realization of Electrically-Switched Dynamic Focused Beam Charging System With a Reconfigurable Phase-Change Cascaded Feed Network for Wireless Power Transfer

A low-cost electrically-switched focused beam charging system based on a reconfigurable phase-change cascaded feed network is introduced for wireless power transfer application. To realize the reconfigurable feed network, we theoretically decomposed the dynamic focusing phase distribution into two independent terms: a linear phase shift and a quadratic term. A focused aperture-coupled patch array antenna with static focused beam is fabricated to achieve the quadratic term. Different linear phase shifts are achieved by using designed electronic switching module to control the beam port status of Rotman lens, enabling to tilt the static focused beam in the desired direction. Based on full-wave simulation and near-field focusing measurement, we analyzed the dynamic focusing performance of generated focused beam with different beam ports excited at 5.758 GHz in detail. Besides, a LED lighting demo experiment for proposed system is carried out for visually displaying the generated dynamic focused beam. The simulation and experiment results indicate that the generated dynamic focused beam tilts as the excitation state of the beam port changes, and its focal spot can be also observed well on the focal plane. The architecture of proposed focused beam system eliminates the need for expensive phase shifters, resulting in a significant reduction in system costs.