The team’s metamaterial, unveiled today in a new paper published in the journal Communications Engineering, could allow future generations of 6G satellites to carry more data, improve their remote sensing ability, and benefit from improved signal quality.
The device could lead to improved satellite communication, high speed data transmission, and remote sensing, scientists say. It could also allow future generations of 6G satellites to carry more data, improve their remote sensing ability, and benefit from improved signal quality.
The team’s breakthrough 2D metamaterial converts the linearly-polarised electromagnetic waves into circular polarisation, which could improve the quality of communication between satellites and ground stations. Satellite communication with circular polarisation offers enhanced reliability and performance, minimising signal degradation from polarisation mismatch and multipath interference.
Circular polarisation is highly resistant to atmospheric effects like rain fading and ionospheric disturbances, ensuring stable connections. It is especially beneficial in mobile applications, as it eliminates the need for precise antenna alignment.
It also doubles channel capacity by using both right-hand and left-hand circular polarisations. This flexibility simplifies antenna design for small satellites, while improving satellite tracking and providing robust communication links in challenging environments, making it ideal for modern satellite systems.
The team’s metamaterial, which is just 0.64mm thick, is made from tiny cells of geometrically-patterned copper, which is laid over a commercial circuit board commonly used in high-frequency communications.
The surface of the metamaterial is designed to allow sophisticated reflection and repolarisation of electromagnetic waves. In lab tests, the 2D metamaterial surface was illuminated by signals from horn antennas and the reflected electromagnetic wave was captured using a network analyser, which allowed the team to measure the effectiveness of the device’s conversion between linear and circular polarisation. The experimental results showed a close resemblance between simulated and experimental measurements for polarisation conversion to circular polarisation.
Their tests also showed that surface is capable of maintaining high performance even when radio signals glance across it at angles of up to 45 degrees – a key consideration for space applications, where perfect alignment between satellites and the surface can be fleeting.
Professor Qammer H. Abbasi, of the University of Glasgow’s James Watt School of Engineering, is the paper’s lead and corresponding author said: “The metamaterial surface we’ve developed works across a wide range of frequencies across the Ku-, K- and Ka-bands, which span 12 GHz to 40Ghz, and are commonly used in satellite applications and remote sensing.
“This kind of 2D metamaterial surface, capable of the complex task of linear to circular polarisation, can enable antennae to communicate with each other more effectively in challenging conditions. It could help satellites provide better signals for phones, and more stable connections for data transmission. It could also improve satellites’ ability to scan the surface of the Earth, improving our understanding of the effects of climate change or our ability to track wildlife migration.”
