Commenced in January 2007
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Protocol Modifications for Improved Co-Channel Wireless LAN Goodput in Partitioned Spaces

Authors: Raymond J. Jayabal, Chiew Tong Lau


Partitions can play a significant role in minimising cochannel interference of Wireless LANs by attenuating signals across room boundaries. This could pave the way towards higher density deployments in home and office environments through spatial channel reuse. Yet, due to protocol limitations, the latest incantation of IEEE 802.11 standard is still unable to take advantage of this fact: Despite having clearly adequate Signal to Interference Ratio (SIR) over co-channel neighbouring networks in other rooms, its goodput falls significantly lower than its maximum in the absence of cochannel interferers. In this paper, we describe how this situation can be remedied via modest modifications to the standard.

Keywords: IEEE 802.11 Wireless LAN, spatial channel re-use, physical layer capture.

Digital Object Identifier (DOI):

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[1] T.S. Rappaport. Wireless Communications: Principles and Practice, 2nd edition. pp. 157-165. New Jersey, Prentice-Hall, 2002.
[2] A. Kochut, A. Vasan, A. Shankar, and A. Agrawala. "Sniffing Out the Correct Physical Layer Capture Model in 802.11b", in Proceedings of IEEE International Conference on Network Protocols (ICNP), Berlin, Germany, October 2004.
[3] G. Sachin, K. Ramachandran, M. Gruteser, I. Seskar, J. Deng, "Methods for Restoring MAC Layer Fairness in IEEE 802.11 Networks with Physical Layer Capture", in Proceedings of the 2nd International Workshop on Multi-Hop Ad Hoc Networks: From Theory to Reality, pp. 7-14, 2006.
[4] Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, IEEE Std 802.11, 2007.
[5] A. Muqattash and M. Krunz, "A Single-Channel Solution for Transmission Power Control in Wireless Ad Hoc Networks", In Proceedings of MobiHoc, 2004.
[6] J. Zhu, X. Guo, L. L. Yang, W.S. Conner, "Leveraging Spatial Reuse in 802.11 Mesh Networks with Enhanced Physical Carrier Sensing", In Proceedings of the IEEE International Conference on Communications (ICC), 2004.
[7] X. Yang and N. H. Vaidya. "On the Physical Carrier Sense in Wireless Ad Hoc Networks". In Proceedings of IEEE INFOCOM, 2005.
[8] A. Vasan, R. Ramjee, and T. Woo. "ECHOS: Enhanced Capacity 802.11 Hotspots". In Proceedings of IEEE INFOCOM, 2005.
[9] J. Fuemmeler, N. H. Vaidya, and V. V. Veeravalli. "Selecting Transmit Powers and Carrier Sense Thresholds for CSMA Protocols". Technical Report, Univ. of Illinois - Urbana Champaign, 2004.
[10] T.S. Kim, J.C. Hou, H. Lim, "Improving Spatial Reuse Through Tuning Transmit Power, Carrier Sense Threshold, and Data Rate in Multihop Wireless Networks". In Proceedings of the 12th Annual International Conference on Mobile Computing and Networking, pp. 366-377, 2006.
[11] J. Zhu, B. Metzler, X. Guo, Y. Liu, "Adaptive CSMA for Scalable Network Capacity in High-Density WLAN: a Hardware Prototyping Approach", in Proceedings of IEEE INFOCOM, pp 1-10, 2006.
[12] X. Yang, N. Vaidya, "Spatial Backoff Contention Resolution for Wireless Networks", in Proceedings of the 2nd IEEE Workshop on Wireless Mesh Networks, pp. 13-22, 2006.
[13] X. Yang, N. Vaidya, "A Spatial Backoff Algorithm Using the Joint Control of Carrier Sense Threshold and Transmission Rate", In Proceedings of the 4th Annual ACM Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON), pp. 501-511, 2007.
[14] A.Akella, G.Judd, P. Steenkiste and S. Seshan. "Self Management in Chaotic Wireless Deployments. In Proceedings of ACM MobiCom, 2005.
[15] B.Sadeghi, V.Kanodia, A.Sabharwal, and E.Knightly, "Opportunistic Media Access for Multirate Ad Hoc Networks", In Proceedings of ACM MobiCom, 2002, pp. 24-35.
[16] M. Cesana, D. Maniezzo, P. Bergamoy, M. Gerla, "Interference Aware (IA) MAC: an Enhancement to IEEE 802.11b DCF", In Proceedings of IEEE Vehicular Technology Conference, 2003.
[17] T. Nadeem, L. Ji, A. Agrawala, J. Agre, "Location Enhancement to IEEE 802.11 DCF", in Proceedings of IEEE INFOCOM, 2005.
[18] The Network Simulator ns-2,
[19] Intersil HFA3863 DSSS Baseband Processor Datasheet (April 2000),
[20] R Jain. The Art of Computer Systems Performance Analysis, John Wiley and Sons, 1991.
[21] C. Hu, H. Kim, and J. C. Hou. "An Analysis of the Binary Exponential Backoff Algorithm in Distributed MAC Protocols", Technical Report, Univ. of Illinois - Urbana Champaign, 2005.