Professor Jiaran Qi’s team, at School of Electronics and Information Engineering, Harbin Institute of Technology,, has made new advancements in the field of microwave wireless power transfer by developing a compact framework. Their research, titled Intelligent Wireless Power Transfer via a 2-bit Compact Reconfigurable Transmissive-Metasurface-Based Router, has been published in Nature Communications. Benefiting from advantages such as low cost and compactness, this framework is expected to promote the application of related devices based on metasurfaces in various fields, including smart homes, implantable medical devices, industrial robots, transportation, and space applications.
The team demonstrated the use of this wireless power transmitter to charge multiple everyday devices, such as LED lights, mobile phones, and power banks. They also showcased simultaneous wireless information and power transfer demonstrations using the transmitter, fully exhibiting the application potential of this wireless power transfer framework.
The team proposed a compact wireless power transfer framework based on reconfigurable transmissive metasurfaces. The core components of this framework include a plane-wave feeder and a 2-bit phase-reconfigurable transmissive metasurface, together forming a multi-beam reconfigurable wireless power transmitter. This transmitter has a sub-wavelength profile (0.8 wavelengths), with an overall size comparable to that of a 27-inch LCD display. By integrating a deep learning-driven environmental sensor, the wireless power transmitter can detect and locate multiple moving devices and simultaneously transmit wireless power and information to them. The plane-wave feeder generates a nearly plane wave-like uniform wavefront in the near-field region, thereby exciting the metasurface, reducing the system profile to a sub-wavelength scale, which is an order of magnitude smaller than current mainstream excitation schemes.
The 2-bit reconfigurable transmissive metasurface consists of 169 unit-cells, enabling precise control of the wavefront phase through a programmable space-time modulation scheme. The combination of the near-field plane-wave feeder and the reconfigurable transmissive metasurface forms a wireless power transmitter capable of wirelessly delivering power to multiple targets, such as smartphones and drones. Additionally, this framework includes an environmental sensor and an intelligent computing unit. The environmental sensor collects dynamic information about the number and location of devices to be charged, while the intelligent computing unit processes the sensor data to generate specific phase patterns to control the wireless power transmitter. Without the need for human intervention, this transmitter can achieve simultaneous wireless information and power transfer to multiple moving targets in random environments.
Paper Link: https://www.nature.com/articles/s41467-024-46984-4
