OFDMA with Resource and Traffic Constraints: Sum Rate Maximization with no CSI

For a specific high-throughput wireless local area network based on OFDM we study the sum rate of time and frequency division multiple access (TDMA, OFDMA). In allocating resources we consider a minimum size of the smallest resource unit that a user can be allotted. We further assume packet switched traffic with most of it carried by only a few large packets. Relatively little data is carried by a large number of small packets. We show that given the resource and traffic constraints the sum rate may be drastically reduced compared to the unconstrained case in TDMA. We also show that by allowing many users to be active simultaneously OFDMA maintains high throughput. In OFDMA we can do time-sharing between two different bandwidth allocations. We derive the number and rates of users in each of the modes to maximize the sum rate.

[1]  Gerhard Fettweis,et al.  Achievable Rates of Asymmetrical Multiple Access in Block-Fading Channels , 2006, 2006 IEEE International Conference on Communications.

[2]  David Kotz,et al.  Analysis of a Campus-Wide Wireless Network , 2002, MobiCom '02.

[3]  Shlomo Shamai,et al.  Fading Channels: Information-Theoretic and Communication Aspects , 1998, IEEE Trans. Inf. Theory.

[4]  Raymond Knopp,et al.  Information capacity and power control in single-cell multiuser communications , 1995, Proceedings IEEE International Conference on Communications ICC '95.

[5]  Abbas Jamalipour,et al.  Wireless communications , 2005, GLOBECOM '05. IEEE Global Telecommunications Conference, 2005..

[6]  Theodore S. Rappaport,et al.  Hotspot traffic statistics and throughput models for several applications , 2004, IEEE Global Telecommunications Conference, 2004. GLOBECOM '04..

[7]  Giuseppe Caire,et al.  Optimum power control over fading channels , 1999, IEEE Trans. Inf. Theory.

[8]  Mary Baker,et al.  Analysis of a local-area wireless network , 2000, MobiCom '00.

[9]  H. Boche,et al.  Queueing theoretic optimal scheduling for multiple input multiple output multiple access channel , 2003, Proceedings of the 3rd IEEE International Symposium on Signal Processing and Information Technology (IEEE Cat. No.03EX795).