A Survey on Multichannel Access Methods in Wireless Networks

PhD Qualifying Examination


Title: "A Survey on Multichannel Access Methods in Wireless Networks"

by

Miss Lu WANG


Abstract:

The fixed spectrum assignment policy limits the efficiency of today’s 
wireless spectrum usage. As the spectrum demand for unlicensed band is 
increasing in recent years, Dynamic Spectrum Access (DSA) in Cognitive 
Radio (CR) networks has been proposed to address the spectrum 
under-utilization problem. DSA allows unlicensed users to share licensed 
spectrum in space and time with little interference to licensed users. 
This idea is originally inspired by Medium Access Control (MAC) designs in 
traditional Multichannel wireless networks, which can reduce interference 
among users as well as improve the spectrum utilization by leveraging 
multiple concurrent transmissions in a set of frequency channels.

Although DSA has improved spectrum usage efficiency by opportunistically 
exploiting the existing wireless spectrum, it shares the same methodology 
with Multichannel MAC protocol in coordinating spectrum access among 
multiple users. Thus their performances are both degraded due to several 
common issues such as Common Control Channel (CCC) Saturation. In order to 
better design DSA in CR networks and bring ideas from traditional wireless 
networks, we firstly review different Multichannel MAC protocols in ad-hoc 
networks by classifying them into four categories based on their operation 
principles. Then we analyze and compare each category with representative 
protocols. Finally we briefly discuss some design challenges when applying 
traditional Multichannel MAC protocols to DSA, and other newly raised ones 
resulting from changing and heterogeneous characteristics of CR networks.


Date:                   Thursday, 31 March 2011

Time:                   2:00pm - 4:00pm

Venue:                  Room 4480
                         lifts 25/26

Committee Members:	Prof. Mounir Hamdi (Supervisor)
                         Dr. Jogesh Muppala (Chairperson)
 			Dr. Lin Gu
 			Prof. Qian Zhang


**** ALL are Welcome ****