A research team from Rice University, in collaboration with partner institutions, has announced a significant breakthrough in wireless communication, paving the way for the future development of 6G networks. The findings, published in Nature Communications Engineering, address a fundamental challenge in high-frequency signal transmission.
As wireless technology advances toward higher frequencies for 6G, networks are poised to transmit massive data at unprecedented speeds, enabling applications like wireless VR and real-time perception systems. However, these high-frequency signals suffer from rapid attenuation in the air and weak penetration power. Unlike traditional Wi-Fi that relies on diffuse signals, 6G requires a precise “line-of-sight” alignment between transmitter and receiver, presenting a major developmental hurdle.
The Rice University team tackled this problem by designing specialized metasurface material. This material can generate electromagnetic wave “fingerprints” with unique directionality within a trillionth of a second. This innovation boosts the angular positioning accuracy for the 6G signal receiver to 0.1 degrees – a tenfold improvement over existing technology. This advance effectively solves the issue of connection interruptions caused by the fast signal attenuation and poor penetration in the terahertz band.The new method also enables near-instantaneous, high-precision alignment. Researchers successfully generated and controlled a radio wave pattern that identifies the signal’s direction with an accuracy of 0.1 degrees. This allows wireless connections to be established almost immediately after the signal is sent, significantly reducing communication latency. Boraç Bilgin, the paper’s first author and a Ph.D. student at Rice University, explained that their method achieves extremely fast angle estimation with unprecedented accuracy. “This enables wireless links to be quickly established or restored with extremely low latency, allowing wireless devices to locate each other more rapidly. This is key to realizing the next generation of high-speed wireless communication,” Bilgin said.
He compared the principle to a lighthouse emitting light of multiple colors with randomly varying intensities. “The wireless transmitter is like a lighthouse, the receiver is like a ship, and the radio waves are like light rays. The receiving end determines its position relative to the lighthouse by observing the unique combination and intensity of the light, as this random distribution is distinct in different directions.”While previous methods typically allowed signal modification in either the time or frequency dimension, but not both, the Rice team used metasurfaces to achieve controllable changes in both dimensions simultaneously. Bilgin elaborated that, continuing the lighthouse analogy, their system is the first to achieve “multicolor and time-varying” signal emission. Because the random “colors” are reshuffled in different time windows, the receiver can obtain more accurate positioning through cumulative observation, even in noisy or bandwidth-constrained environments.
Researchers emphasize that as wireless communication moves into the terahertz band, such high-precision positioning is crucial. The experiment required processing vast amounts of data to analyze the statistical properties of random signals, with collaborators from Brown University providing support for theoretical modeling and electromagnetic behavior simulations. Bilgin described the work as a study on “programmable randomness.” The team collected extensive data to analyze its average characteristics. “The entire process required careful planning and scheduling. Although we encountered unexpected situations, such as experiments being interrupted by power outages, it was worthwhile to see that the results matched our predictions,” he noted. Edward Knightly, a professor of electrical and computer engineering and computer science at Rice University, stated that this research demonstrates how future wireless networks can cope with the ever-growing demand for data. “The physical characteristics of signals determine the network’s capabilities. This research transforms challenges into opportunities, proving that designed randomness can make wireless networks faster, smarter, and more reliable,” Knightly said. The research received support from Cisco and Intel and was funded by the National Science Foundation and the Los Alamos and Sandia National Laboratories under the U.S. Department of Energy’s Office of Science.