Cognitive radios, which have the ability to adjust bandwidth, modulation scheme, transmit power, error coding, and other parameters, provide tremendous flexibility for adaptation to network conditions. While cognitive radios predominantly change spectral allocation or modulation characteristics, this project considers networks of cognitive radios in which the antennas at each node can be electronically reconfigured. Coupling cognitive radios with reconfigurable antennas gives network nodes an additional degree of freedom to increase link robustness, enhance interference suppression, and increase spectral capacity.
This project demonstrates how the flexibility in radiation patterns provided by electrically reconfigurable antennas, or ?cognitive antennas?, can enable a greater density of co-channel communication links and thus increase network capacity. Multi-sensor data fusion is being used to incorporate antenna and radio configuration with cognitive radio scene assessment and adaptation techniques, using multiple data sources. Distributed control techniques are being developed to adapt cognitive radio settings with minimum interaction between nodes, and and the stability and convergence of these algorithms (including convergence rate) are analyzed. We are also creating practical networking protocols to include cognitive antenna capabilities in QoS routing, congestion control, path failure mitigation, and resource management. Research results are being demonstrated on a hardware testbed. The main result of this project is a framework for controlling cognitive radios equipped with reconfigurable antennas.
The proposal fosters technical innovation and design among undergraduate students, and outreach activities to attract students, especially from under-represented groups, to engineering.
