SpringerOpen Newsletter

Receive periodic news and updates relating to SpringerOpen.

This article is part of the series Radio Resource Management in 3G+ Systems.

Open Access Open Badges Research Article

Opportunistic Nonorthogonal Packet Scheduling in Fixed Broadband Wireless Access Networks

Mahmudur Rahman1*, Halim Yanikomeroglu1, Mohamed H Ahmed2 and Samy Mahmoud1

Author Affiliations

1 Communications and Wireless Systems (BCWS) Centre, Department of Systems and Computer Engineering, Carleton University, Ottawa, Ontario, Canada, K1S 5B6

2 Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John's, NL, Canada, A1B 3X5

For all author emails, please log on.

EURASIP Journal on Wireless Communications and Networking 2006, 2006:080493  doi:10.1155/WCN/2006/80493

The electronic version of this article is the complete one and can be found online at: http://jwcn.eurasipjournals.com/content/2006/1/080493

Received:14 October 2005
Revisions received:11 March 2006
Accepted:13 March 2006
Published:18 June 2006

© 2006 Rahman et al.

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

In order to mitigate high cochannel interference resulting from dense channel reuse, the interference management issues are often considered as essential part of scheduling schemes in fixed broadband wireless access (FBWA) networks. To that end, a series of literature has been published recently, in which a group of base stations forms an interferer group (downlink transmissions from each base station become dominant interference for the users in other in-group base stations), and the scheduling scheme deployed in the group allows only one base station to transmit at a time. As a result of time orthogonality in transmissions, the dominant cochannel interferers are prevented, and hence the packet error rate can be improved. However, prohibiting concurrent transmissions in these orthogonal schemes introduces throughput penalty as well as higher end-to-end packet delay which might not be desirable for real-time services. In this paper, we utilize opportunistic nonorthogonality among the in-group transmissions whenever possible and propose a novel transmission scheduling scheme for FBWA networks. The proposed scheme, in contrast to the proactive interference avoidance techniques, strives for the improvements in delay and throughput efficiency. To facilitate opportunistic nonorthogonal transmissions in the interferer group, estimation of signal-to-interference-plus-noise ratio (SINR) is required at the scheduler. We have observed from simulations that the proposed scheme outperforms the reference orthogonal scheme in terms of spectral efficiency, mean packet delay, and packet dropping rate.


  1. IEEE Std. 802.16a for Local and Metropolitan Area Networks, Air interface for fixed broadband wireless access systems, IEEE, April 2003

  2. H Bölcskei, AJ Paulraj, KVS Hari, RU Nabar, WW Lu, Fixed broadband wireless access: state of the art, challenges, and future directions. IEEE Communications Magazine 39(1), 100–108 (2001). Publisher Full Text OpenURL

  3. DL Waring, The asymmetrical digital subscriber line (ADSL): a new transport technology for delivering wideband capabilities to the residence. Proceedings of IEEE Global Telecommunications Conference and Exhibition (GLOBECOM '91), December 1991, Phoenix, Ariz, USA 3, 1979–1986

  4. K Maxwell, Asymmetric digital subscriber line (ADSL): interim technology for the next forty years. IEEE Communications Magazine 34(10), 100–106 (1996). Publisher Full Text OpenURL

  5. C Bisdikian, K Maruyama, DI Seidman, DN Serpanos, Cable access beyond the hype: on residential broadband data services over HFC networks. IEEE Communications Magazine 34(11), 128–135 (1996). Publisher Full Text OpenURL

  6. P Bhagwat, P Bhattacharya, A Krishna, SK Tripathi, Enhancing throughput over wireless LANs using channel state dependent packet scheduling. Proceedings IEEE of 15th Annual Joint Conference of the IEEE Computer Societies (INFOCOM '96), March 1996, San Francisco, Calif, USA 3, 1133–1140

  7. TSE Ng, I Stoica, H Zhang, Packet fair queueing algorithms for wireless networks with location-dependent errors. Proceedings of IEEE 17th Annual Joint Conference of the IEEE Computer and Communications Societies (INFOCOM '98), March-April 1998, San Francisco, Calif, USA 3, 1103–1111

  8. S Desilva, SM Das, Experimental evaluation of channel state dependent scheduling in an in-building wireless LAN. Proceedings of 7th International Conference on Computer Communications and Networks (ICCCN '98), October 1998, Lafayette, La, USA, 414–421

  9. C Fragouli, V Sivaraman, MB Srivastava, Controlled multimedia wireless link sharing via enhanced class-based queuing with channel-state-dependent packet scheduling. Proceedings of IEEE 17th Annual Joint Conference of the IEEE Computer and Communications Societies (INFOCOM '98), March-April 1998, San Francisco, Calif, USA 2, 572–580

  10. S Lu, V Bharghavan, R Srikant, Fair scheduling in wireless packet networks. IEEE/ACM Transactions on Networking 7(4), 473–489 (1999). Publisher Full Text OpenURL

  11. TK Fong, PS Henry, KK Leung, X Qiu, NK Shankaranarayanan, Radio resource allocation in fixed broadband wireless networks. IEEE Transactions on Communications 46(6), 806–818 (1998). Publisher Full Text OpenURL

  12. MH Ahmed, H Yanikomeroglu, S Mahmoud, Interference management using packet sheduling in broadband wireless access networks. Willey Journal on Wireless Communications and Mobile Computing 6(1), 95–103 (2006). Publisher Full Text OpenURL

  13. MH Ahmed, H Yanikomeroglu, S Mahmoud, DD Falconer, Scheduling of multimedia traffic in interference-limited broadband wireless access networks. Proceedings of 5th International Symposium on Wireless Personal Multimedia Communications (WPMC '02), October 2002, Honolulu, Hawaii, USA

  14. KK Leung, A Srivastava, Dynamic allocation of downlink and uplink resource for broadband services in fixed wireless networks. IEEE Journal on Selected Areas in Communications 17(5), 990–1006 (1999). Publisher Full Text OpenURL

  15. F Borgonovo, M Zorzi, L Fratta, V Trecordi, G Bianchi, Capture-division packet access for wireless personal communications. IEEE Journal on Selected Areas in Communications 14(4), 609–622 (1996). Publisher Full Text OpenURL

  16. K Chawla, X Qiu, Quasi-static resource allocation with interference avoidance for fixed wireless systems. IEEE Journal on Selected Areas in Communications 17(3), 493–504 (1999). Publisher Full Text OpenURL

  17. X Liu, EKP Chong, NB Shroff, Opportunistic transmission scheduling with resource-sharing constraints in wireless networks. IEEE Journal on Selected Areas in Communications 19(10), 2053–2064 (2001). Publisher Full Text OpenURL

  18. M Rahman, in Adaptive modulation & coding-based packet scheduling with inter-base station coordination in cellular fixed broadband wireless networks, M, ed. by . S. thesis (Carleton University, Ottawa, Ontario, Canada, 2004) (http://www, 2004), . sce.carleton.ca/faculty/yanikomeroglu/cv/publications.shtml webcite PubMed Abstract | PubMed Central Full Text OpenURL

  19. OPNET University Program: http://www.opnet.com/services/university

  20. V Erceg, LJ Greenstein, SY Tjandra, et al. An empirically based path loss model for wireless channels in suburban environments. IEEE Journal on Selected Areas in Communications 17(7), 1205–1211 (1999). Publisher Full Text OpenURL

  21. V Erceg, et al. Channel models for fixed wireless applications (IEEE 802), . 16 work in progress document # 802.16.3c-01/29r4, July 2001

  22. CR Baugh, J Huang, Traffic model for 802.16 TG3 MAC/PHY simulations (IEEE 802), . 16 work in progress document # 802.16.3c-01/30r1, March 2001