Collaborative Communication for Cognitive Radio Applications
Ben Juda Wild and Kannan Ramchandran
National Science Foundation
It is well known that wireless spectrum is vastly under-utilized. In our previous work, we attempted to re-use spectrum by dynamically sensing receivers, and re-using bands where no receivers were tuned to . Currently, our focus has shifted to using collaborative beamforming among cognitive radios to use the spatial dimension efficiently . In  we describe the world's first experimental distributed beamforming testbed. Using this testbed, we have shown that N collaborating radios can in fact achieve beamforming gains proportional to N2.
- B. Wild and K. Ramchandran, "Detecting Primary Receivers for Cognitive Radio Applications," Proc. Dynamic Spectrum Access Networks, November 2005.
- R. Mudumbai, B. Wild, U. Madhow, and K. Ramchandran, "Distributed Beamforming Using 1 Bit Feedback: from Concept to Realization," Proc. Allerton Conf. Communication, Control and Computing, September 2006.