University of Texas

Academic investigations are establishing the future
 of transmission technology for troops and civilians.

Improving antennas for defense or commercial purposes has as much to do with mathematics as it does with hardware. Researchers in the Wireless Networking and Communications Group at the University of Texas at Austin are exploring algorithms along with other properties that should improve communications systems on the battlefield.

A key focus of the work has honed in on multiple input, multiple output (MIMO) technology, which features many transmit and receive antennas. A large portion of that effort involves studying limited feedback—an idea that if receivers can send information back to an original transmitter, that transmitter can better configure links. This process should reduce interference and has applications for MIMO and cellular communications. Dr. Robert W. Heath Jr., director of the Wireless Networking and Communications Group (WNCG), says the research has advanced beyond single point-to-point links to examine how base stations can connect to many users and how to coordinate multiple base stations together to reduce interference.

Team members are looking into the fundamental limitations of such systems, and their results demonstrate that complete elimination of interference is not feasible only through the coordination of base stations. “That’s been something that’s surprising,” Heath states. Graduate students under his direction also are studying new analysis techniques in which they try to understand system performance and how antennas would play a role in situations with randomly located base stations. On the cellular side, experiments are underway to see how antennas can improve facets of functionality. Team members are exploring how distributing antennas throughout the cell instead of locating them all at the base station impacts performance.