Title: Interference Modeling in Random Carrier-Sense Multiple Access Wireless Networks
Date: April 3, 2013
Time: 10:00 – 11:00 am
Location: ICT516, University of Calgary

Abstract:
In random networks, point processes are used to statistically describe the spatial distribution of the network nodes. A common and analytically tractable assumption is that the nodes are distributed in the space according to a homogeneous Poisson point process (PPP). Then the aggregate interference is obtained using the shot noise theory. However, a PPP cannot be directly used to model the spatial distribution of interference sources when modeling aggregate interference in random networks using carrier-sense multiple access (CSMA). This is because, using PPP does not forbid any two points of the process to coexist within a distance less than a certain value. This distance reflects the sensing range of the CSMA protocol and defines an exclusion region around a receiver. Hard core point process (HCPP) is one form of the point processes that has been used to model the spatial distribution of interferers in CSMA networks. However, HCPP suffers from two major drawbacks. First, it highly underestimates the number of the interferers existing in the network, hence, underestimates the resultant aggregate interference. Second, since HCPP is no longer a PPP, the well-known formulas available in the literature for the PPP do not apply to it.

In this talk, I will present a modified HCPP model to eliminate the underestimation problem and obtain the intensity of the modified HCPP (MHCPP). Subsequently, closed-form approximate expressions for the moment generating function, mean and variance of the associated aggregate interference will be obtained. The accuracy of the MHCPP modeling and the aggregate interference approximation will be validated. Extension of the model for the generalized fading environments will be also discussed. The proposed modeling approach can be used for networks including cognitive femtocell and other small cell networks.

Biography:
Ekram Hossain is a Professor in the Department of Electrical and Computer Engineering at University of Manitoba, Winnipeg, Canada. He received his Ph.D. in Electrical Engineering from University of Victoria, Canada, in 2001. Dr. Hossain’s current research interests include design, analysis, and optimization of wireless/mobile communications networks, cognitive radio systems, and network economics. He has authored/edited several books in these areas (http://www.ee.umanitoba.ca/~ekram). Dr. Hossain currently serves as the Editor-in-Chief for the IEEE Communications Surveys and Tutorials, an Editor for the IEEE Journal on Selected Areas in Communications – Cognitive Radio Series, and an Editor for IEEE Wireless Communications. Also, he serves on the IEEE Press Editorial Board (for the term 2013-2015). Previously, he served as the Area Editor for the IEEE Transactions on Wireless Communications in the area of “Resource Management and Multiple Access” from 2009-2011 and an Editor for the IEEE Transactions on Mobile Computing from 2007-2012. Dr. Hossain has won several research awards including the University of Manitoba Merit Award in 2010 (for Research and Scholarly Activities), the 2011 IEEE Communications Society Fred Ellersick Prize Paper Award, and the IEEE Wireless Communications and Networking Conference 2012 (WCNC’12) Best Paper Award. He is a Distinguished Lecturer of the IEEE Communications Society for the term 2012-2013. Dr. Hossain is a registered Professional Engineer in the province of Manitoba, Canada.

For further information contact Stephen Lai.