Research Projects

Performance Analysis of Multichannel Medium Access Control Algorithms for Opportunistic Spectrum Access

Ahmad Bahai, Przemysław Pawełczak¹ and Sofie Pollin

MICRO, European Commission and Interuniversity Micro-Electronics Center (IMEC)

In this project different ways of control channel implementation for multichannel Medium Access Control (MAC) algorithms for Opportunistic Spectrum Access (OSA) are compared and analyzed, as a function of spectrum sensing performance and licensed users activity. The comparison is based on a proposed discreet Markov chain model of certain multichannel OSA MAC classes, incorporating physical layer effects like spectrum sensing and fading, and extensive simulations. The major conclusions are as follows: a) When the control channel is implemented through a dedicated channel, sharing that dedicated channel with the licensed user does not significantly decrease the throughput achieved by the OSA network, when the data packet sizes are sufficiently large or the number of considered data channels small; b) Hopping OSA MACs, where the control channel is spread over all channels, are less susceptible to licensed user activity than those with a dedicated control channel (both in terms of average utilization and on/off times); c) Scanning performance has a large impact on the achievable performance of licensed and OSA users for all analyzed protocols; d) The Multiple Rendezvous MAC class, which has not been proposed in the OSA literature yet, outperforms all multichannel MAC designs analyzed in this paper.

[1]

P. Pawełczak, S. Pollin, H-S. W. So, A. Motamedi, A. Bahai, R.V. Prasad, R. Hekmat, Quality of Service of Opportunistic Spectrum Access: A Medium Access Control Approach, IEEE Wireless Communications, accepted for publication, 10 Jun. 2008

[2]

P. Pawełczak, S. Pollin, H-S. W. So, A. Bahai, R.V. Prasad, R. Hekmat, Comparison of Opportunistic Spectrum Multichannel Medium Access Control Protocols, in Proc. 51st IEEE Global Telecommunications Conference (IEEE GLOBECOM 2008), 30 Nov. - 4 Dec. 2008, New Oreleans, LA, USA

[3]

P. Pawełczak, S. Pollin, H-S. W. So, A. Motamedi, A. Bahai, R.V. Prasad, R. Hekmat, State of the Art in Opportunistic Spectrum Access Medium Access Control Design, in Proc. 3rd ICST/IEEE International Conference on Cognitive Radio Oriented Wireless Networks and Communications (ICST/IEEE CrownCom 2008 Conference), 15-17 May 2008, Singapore 2008 [Invited Paper]

¹TU Delft