Engineers from Penn State University have developed a material that allows them to control the frequency response and polarization of extremely small satellite antennas. Their experiments could result in the development of high-performance antennas that can switch between low and high frequency bands.
This project represents one of the latest advances in the study of metamaterials—synthetic materials whose unique properties have astounded and frustrated scientists trying to exploit them. The properties of metamaterials are the result of tiny internal structures, which can be exploited to control light, sound, and radio waves in unnatural ways.
Publishing their results in the journal Advanced Electronic Materials, the engineers outlined a metamaterial-based antenna that can operate over an unprecedented bandwidth. The engineers found that by simultaneously tuning the metamaterial and a software-defined radio, they could operate the antenna across a wider bandwidth than would normally be possible.
“Metamaterial-based antennas often suffer a stigma of impractically narrow operating bandwidths, just like small antennas,” said Clinton Scarborough, who worked on the project. “The laws of physics dictate that a small metamaterial antenna will have a small bandwidth,” he said.
Scarborough said the tunable metamaterial can extend an antenna with narrow instantaneous bandwidth across an entire communications band. His experiments showed that, combined with a software-defined radio, the metamaterial antenna had similar performance to a large broadband antenna.
Douglas H. Werner, a study co-author and professor of electrical engineering at Penn State, said that tuning “the metamaterial and antenna in tandem provides a dynamic operating channel, with a tunable, nearly-arbitrary polarization response as an added benefit.”