Collaborative Research: EARS: Interference mitigation by stream decomposition enabled by liquid-metal adaptive antennas

University Of Texas At Dallas, Richardson TX

Investigators

Abstract

Interference between users is one of the main impediments for the growth of wireless networks such as the ones used by mobile phones. Developing practical methods to mitigate interference is critical for the future of wireless technology. The proposed research addresses the problem of interference, and therefore has a large potential impact on economic growth as well as quality of life. This project has two interconnected components. First, based on recent information theory results, communication streams will be decomposed into many small streams; these can be managed, combined, and split to combat interference. Second, adaptive liquid-metal antennas will be investigated for interference mitigation. As liquid metals can be made to change their physical shape, they can enable antennas that can be adjusted to reduce interference. Research and education for this project will be tightly integrated through Vertically Integrated Projects that involve students ranging from PhD students to sophomore-level undergraduates, including under-represented minority and female students. The results of this research will be disseminated widely through the web, technical conferences, and seminars. Exciting discoveries in recent years have pushed the boundaries of understanding interference. The theoretical capacity of interference channels in several operating modes has been established, and new theoretical techniques such as interference alignment have been discovered. However, many practical challenges stand in the way of realizing these promising techniques. This project has two interconnected components for developing interference-mitigation techniques for wireless networks that create a new direction in interference mitigation aimed at practicality and wide applicability. The first component of the project decomposes the communication stream into "microstreams" to fit the transmissions into the contours of available opportunities, in a manner that improves rates while limiting the damage of interference. The broad principle of breaking communication into many small pieces has a long and distinguished pedigree, including ARQ in the data link layer and TCP/IP in higher layers. The proposed research introduces a novel manifestation of this time-tested principle to produce new approaches that combat interference in the physical layer. The second component of the project investigates adaptive liquid-metal antennas that generate radiation patterns to avoid interference in a manner not possible with signal processing alone; in particular their unique flexibility helps to avoid "singular" values of channel gains that prevent interference mitigation. The unique strengths of liquid-metal antennas are perfectly showcased in this application, because the exact manner of microstream combining can have a strong effect on performance, and this is where liquid-metal antennas promise to have a strong impact. The proposed activity will play an important role in the advancement of knowledge and understanding in the field of wireless interference. The project will develop practical methods for coding and decoding under interference. Furthermore, it will lead to a basic understanding of how liquid-metal antennas can affect capacity in interference networks.