IEEE Winnipeg Section


UofM CS Department Seminar



Interference Modeling in Random Carrier-Sense Multiple Access (CSMA)
Wireless Networks: A Stochastic Geometry Approach


Thursday, October 20, 2011 at 1:00pm


E2-304 EITC Building, University of Manitoba Fort Garry Campus


Ekram Hossain, Ph.D.
Department of Electrical and Computer Engineering,
University of Manitoba


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 with collision avoidance (CSMA/CA). This is because using PPP forbids 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/CA protocol and defines an exclusion region around a receiver. Hard core point process (HCPP), introduced by Matern in 1960, is one form of the point processes that has been used to model the spatial distribution of interferers in CSMA/CA 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. Secondly, HCPP is no longer a PPP; hence, 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.

Speaker Bio:

Dr. 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 main research interest lies in resource allocation and multiple-access in wireless/mobile communications networks and cognitive radio systems. The books Dynamic Spectrum Access and Management in Cognitive Radio Networks (Cambridge University Press, 2009) and Cognitive Wireless Communication Networks (Springer, 2007, ISBN: 978-0-387-68830-5) are two of his important contributions in these areas. Currently he serves as the Area Editor for the IEEE Transactions on Wireless Communications in the area of “Resource Management and Multiple Access”, an Editor for the IEEE Transactions on Mobile Computing, the IEEE Communications Surveys and Tutorials, and IEEE Wireless Communications. He has been appointed the Editor-in-Chief for the IEEE Communications Surveys and Tutorials for the term 2012-2013. Dr. Hossain has several research awards to his credit, which include the University of Manitoba Merit Award in 2010 (for Research and Scholarly Activities) and the 2011 IEEE Communications Society Fred Ellersick Prize Paper Award. He is a registered Professional Engineer in the province of Manitoba, Canada.


This will be a free event.


If you would like additional information or if you might be interested in presenting a seminar, please contact Stephane Durocher or the Department of Computer Science.

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