Cognitive radios achieve opportunistic use of underutilized spectrum by sensing and using frequency bands only if no primary user is detected. Previous approaches to spectrum sensing have examined one band at a time. We argue that this ignores the sparsity inherent to the problem: not only are a large fraction of bands unused, but the number of primary antenna sites is far smaller than the numb...

We provide an overview of the main results that we obtained studying uncertain mixed integer linear programs when the uncertainty is represented through the new multiband model [4]. Such model extends and refines the classical one proposed by Bertsimas and Sim [2] and is particularly suitable in the common case of arbitrary non-symmetric distributions of the uncertainty. Our investigations were...

Multiband Absorber In article number 2000734 by Guangsheng Deng, Jun Yang, and co-workers, a multiband absorber based on three-dimensional (3D) frequency selective structures (FSSs) is presented. Four standing closed loops intersecting with lateral split loop in each cell, as shown the bottom of picture, generate multi-band perfect electromagnetic wave absorption. The proposed structure, which ...