To increase spectrum utilization, cognitive radios can detect and share the unused spectrum. However, each cognitive radio can only scan a narrow band of spectrum, and the scan is time consuming. This bottleneck limits spectrum sensing in terms of bandwidth, speed, and accuracy. Aiming at breaking this bottleneck, we propose compressive collaborative spectrum sensing based on the recent technique of compressive sensing, which senses less and computes more. It lets a sensor acquire a signal, not by taking many samples, but rather by measuring a few incoherent linear projections. The sensor transmits the linear projections to a receiver, where the signal is reconstructed by an algorithm. For many applications, such a shift of resource demands from pre-transmission to post-transmission can be of great benefit. This is true for spectrum sensing, where the benefit is less and faster sensing at the cognitive radio nodes, as well as reduced transmission from these nodes to the fusion center.
Zhu Han received the B.S. degree in electronic engineering from Tsinghua University, in 1997, and the M.S. and Ph.D. degrees in electrical engineering from the University of Maryland, College Park, in 1999 and 2003, respectively. From 2000 to 2002, he was an R&D Engineer of JDSU, Germantown, Maryland. From 2003 to 2006, he was a Research Associate at the University of Maryland. From 2006 to 2008, he was an assistant professor in Boise State University, Idaho. Currently, he is an Assistant Professor in Electrical and Computer Engineering Department at University of Houston, Texas. In June-August 2006, he was a visiting scholar in Princeton University. In May-August 2007, he was a visiting professor in Stanford University. In May-August 2008, he was a visiting professor in University of Oslo, Norway and Supelec, Paris, France. In July 2009, he was a visiting professor in the University of Illinois at Urbana- Champion. In June 2010, he visited the University of Avignon, France. His research interests include wireless resource allocation and management, wireless communications and networking, game theory, wireless multimedia, and security. Dr. Han is an NSF CAREER award recipient 2010. Dr. Han has 2 best paper awards (ICC09 and Wiopt 09), and winner of Fred W. Ellersick Prize 2011.