Nabil Giweli, Seyed Shahrestani and Hon Cheung
School of Computing, Engineering and Mathematics, Western Sydney University,
Sydney, Australia
ABSTRACT
The rapidly growing number of wireless devices running applications that require high bandwidths, has
resulted in increasing demands for the unlicensed frequency spectrum. Given the scarcity of allocated
unlicensed frequencies, meeting such demands can become a serious concern. Cognitive Radio (CR)
technology opens the door for the opportunistic use of the licensed spectrum to partially address the issues
relevant to the limited availability of unlicensed frequencies. Combining CR and Wi-Fi to form the socalled
White-Fi networks, has been proposed for achieving higher spectrum utilization. This article
discusses the spectrum sensing in White-Fi networks and the impacts that it has on the QoS of typical
applications. It also reports the analysis of such impacts through various simulation studies. Our results
demonstrate the advantages of an adaptive sensing strategy that is capable of changing the related
parameters based on QoS requirements. We also propose such a sensing strategy that can adapt to the
IEEE 802.11e requirements. The goal of the proposed strategy is the enhancement of the overall QoS of the
applications while maintaining efficient sensing of the spectrum. Simulation results of the scenarios that
implement the proposed mechanisms demonstrate noticeable QoS improvements compared to cases where
common sensing methods are utilized in IEEE802.11 networks.
KEYWORDS
Cognitive Radio, IEEE 802.11af, IEEE 802.11e, QoS, Spectrum Sensing, White-Fi.
No comments:
Post a Comment