A metasurface antenna with adaptive frequency control enhances wireless communication capacity, paving the way for future technologies such as 6G.
Wi-Fi 7, 6G cellular networks, and terahertz communications are often seen as the vanguard of emerging wireless technologies. Enabling these advancements — antennas — rarely get the spotlight. Without well-designed antennas, these technologies would falter, affecting applications across IoT, edge AI, and beyond.While methods like nonlinear bulk media and electro-optic modulators have been explored for flexible frequency control, they remain inefficient, complex, and impractical for real-world deployment. Recognizing this, the researchers turned to metasurfaces—materials known for precise electromagnetic wave control but hindered by inefficiencies in harmonic manipulation.
Researchers at the City University of Hong Kong are changing that narrative with an innovative antenna that addresses tomorrow’s communication challenges. Traditional antennas operate with fixed properties, limiting their adaptability. In contrast, the team’s new antenna design can dynamically control multiple frequency components, significantly enhancing channel capacity and enabling simultaneous transmission of signals in different directions.
The team’s waveguide-integrated metasurface antenna, which adopts a synthetic moving-envelope design. Using spatiotemporal modulation — where time acts as a new degree of freedom — the antenna manipulates electromagnetic waves with unprecedented precision. It employs meta-atoms with 1-bit ON-OFF digital switching to construct synthetic sinusoidal moving envelopes, each tied to specific harmonic frequencies.This design allows the antenna to simultaneously generate and control multiple harmonic orders while regulating their wave properties and power distribution. Integrated positive-intrinsic-negative diodes enhance frequency precision and suppress unwanted harmonics, delivering cleaner, high-quality signals.
The antenna can perform tasks like unidirectional frequency conversion, frequency comb generation, and frequency-division multiplexing. This versatility makes it ideal for wireless communications, spectroscopy, and even quantum systems. Its waveguide integration ensures efficient transformation of guided waves into free-space radiation while minimizing interference. Thi could redefine antenna technology, sparking further breakthroughs with metasurfaces. As the demand for high-speed, adaptable communications grows, solutions like this shape-shifting antenna may soon be at the heart of future wireless networks.
