Scientists develop revolutionary metasurface for precise wireless signal control

a The metasurface model. b Unit cell rotation controlled for the polarization conversion function. c Space controlled by blue DC motors for beam scanning functions. Credit: Microsystems & Nanoengineering.

Researchers have recently made a significant breakthrough in wireless communication technology with the development of a new device known as a reconfigurable transmissive metasurface.

This innovative technology, detailed in a study published in Microsystems & Nanoengineering, offers precise control over wireless signals, enhancing their strength and efficiency.

A metasurface is essentially a flat surface made up of an array of elements that can manipulate electromagnetic (EM) waves—these are the waves used in radar systems, wireless networks, and similar technologies.

By changing characteristics like the wave’s amplitude, phase, and polarization, metasurfaces can greatly improve how these systems perform.

The key feature of this new metasurface is its ability to independently control two important aspects of EM waves: their direction and their polarization. Polarization refers to the orientation of the wave’s vibrations; it is crucial for the wave’s interaction with various media and devices. The ability to control the direction of the wave, or beam scanning, allows for targeting specific areas or directions, which is vital in applications like radar and high-resolution imaging.

Traditionally, metasurfaces faced challenges such as limited scanning ranges and difficulty in independently managing wave direction and polarization, affecting their effectiveness and cost-efficiency.

The newly developed metasurface from Chung-Ang University tackles these issues using a unique combination of two types of actuators: scissor and rotation. Scissor actuators adjust the spacing between the elements of the metasurface, while rotation actuators change their orientation.

This setup allows for seamless transitions between different polarization states and the ability to direct beams across a broad area without the constraints found in older systems.

This dual-action control is a breakthrough because it allows the metasurface to switch between right-handed and left-handed circular polarizations and scan beams over a 28-degree range at an operational frequency of 10.5 GHz. These capabilities were demonstrated through extensive testing, including analytical, numerical, and experimental approaches.

Sungjoon Lim, the senior researcher on the project, highlighted the significance of this advancement, stating, “Our work represents a significant step forward in the manipulation of electromagnetic waves.

By combining scissor and rotation actuators, we have developed a metasurface that can independently control beam scanning and polarization conversion, a capability that was previously challenging to achieve.”

This development has broad implications for improving radar systems, wireless communication, and high-resolution imaging, promising to bring new levels of efficiency and effectiveness to these fields.