Time-critical and delay-sensitive multimedia applications require more spectrum and
transmission resources. With the provision of cognitive radios (CRs), the underutilized …

Wireless networks with their ubiquitous applications have become an indispensable part of
our daily lives. Wireless networks demand more and more spectral resources to support the …

Internet of things (IoT) paradigm poses new challenges to the communication technology as
numerous heterogeneous objects will need to be connected. To address these issues new …

The majority of work in cognitive radio networks have focused on single-hop networks with
mainly challenges at the physical and MAC layers. Recently, multi-hop secondary networks …

Dynamic spectrum access is a new spectrum sharing paradigm that allows secondary users
to access the abundant spectrum holes or white spaces in the licensed spectrum bands …

Fueled by ongoing and increasing consumer demand, the explosive growth in spectrum-
based communications continues to tax the finite resources of the available spectrum. One …

Cognitive radio networks (CRNs) are composed of cognitive, spectrum-agile devices
capable of changing their configurations on the fly based on the spectral environment. This …

Traditional spectrum allocation policies may result in temporarily unused radio spectrum.
Cognitive radio (CR) has emerged as a promising technology to exploit the radio spectrum …

In the past decade, cognitive radio and cooperative communication techniques have been
proposed in the literature for efficiently utilizing the radio resources. Cognitive radio is an …

This article provides a comprehensive survey of cognitive radio technology, focusing on its
application to dynamic spectrum access, especially from the perspective of realizing …