Throughput Maximizing Frequency and Power Scheduling for Wireless Ad-Hoc Networks in the Low-SINR Regime
- 1 Division of Engineering and Applied Sciences, Harvard University, Cambridge, USA
Abstract
We study the problem of frequency and power allocation and scheduling at a time-slotted cognitive ad-hoc wireless network, where cognitive nodes share a number of frequency bands and frequency reuse is allowed. In such a network the throughput maximization problem generally results in a mixed zero-one nonlinear non-convex problem. Interestingly, in the low-SINR regime, the power allocation policy that maximizes the total throughput follows an “on/off” strategy with maximum power usage in the “on” state. In this paper we show that the on/off strategy in the low-SINR regime is also optimal with respect to throughput when scheduling users over time and frequency subject to minimum SINR requirements. We show that these additional constraints will not change the optimum strategy, but may affect the set of “on” or “off” transmitters. Also we present an approach that transforms the mixed zero-one nonlinear problem to an equivalent mixed zero-one linear problem at the expense of extra variables.
- J. Bazerque and G. Giannakis, “A Distributed Scheduling and Resource Allocation for Cognitive OFDMA Radios Bazerque,” Proceedings of International IEEE Confer-ence on Cognitive Radio Oriented Wireless Networks and Communications, Orlando, 3 August 2007, pp. 343-350.
- R. Cruz and A. Santhanam, “Optimal Routing, Link Scheduling and Power Control in Multi-Hop Wireless Net-Works,” Proceedings of IEEE INFOCOM, San Francisco, 1-3 April 2003, pp. 702-711.
- G. Foschini and Z. Miljanic, “A Simple Distributed Autonomous Power Control Algorithm and Its Convergence,” IEEE Transactions on Vehicular Tech-nology, Vol. 42, No. 4, 1993, pp. 641-646. doi:10.1109/25.260747
- M. Chiang, C. W. Tan, D. Palomar, D. O’Neill and D. Julian, “Power Control by Geometric Programming,” IEEE Transactions on Wire-less Communications, Vol. 7, 2007, pp. 2640-2651. doi:10.1109/TWC.2007.05960
- B. Babadi and V. Tarokh, “A Distributed Asynchronous Algorithm for Spectrum Sharing in Wireless Ad-Hoc Networks,” Proceedings of 42nd Annual Conference on Information Sciences and Systems, Princeton, 19-21 March 2008. doi:10.1109/CISS.2008.4558635
- R. Urgaonkar and M. J. Neely, “Opportunistic Scheduling with Reliability Guarantees in Cognitive Radio Networks,” Proceedings of IEEE INFOCOM, Phoenix, 13-18 April 2008.
- Y. Y. T. Hou, Y. Shi and H. Sherali, “Optimal Spectrum Sharing for Multi-Hop Software Defined Radio Net-works,” Proceedings of IEEE INFOCOM, Anchorage, 6-12 May 2007.
- Y. Yuan, P. Bahl, R. Chandra, T. Moscibroda and Y. Wu, “Allocating Dynamic Time-Spectrum Blocks in Cognitive Radio Networks,” Proceedings of IEEE/ACM MobiHoc, Montreal, 9-14 September 2007.
- C. Peng, H. Zheng and B. Y. Zhao, “Utilization and Fairness in Spectrum Assignment for Opportunistic Spectrum Access,” ACM Mobile Net-works and Applications, Vol. 11, No. 4, 2006, pp. 555-576. doi:10.1007/s11036-006-7322-y
- M. Ebrahimi, M. A. Maddah-Ali and A. K. Khandani, “Throughput Scaling Laws for Wireless Networks with Fading Channels,” IEEE Transactions on Information Theory, Vol. 113, No. 2-3, 2007, pp. 4550-4554.
- J. Tang, G. Xue, C. Chandler and W. Zhang, “Link Scheduling with Power Control for Throughput Enhancement in Multihop Wireless Networks,” IEEE Transactions on Vehicular Technology, Vol. 55, No. 3, 2006, pp. 733-742. doi:10.1109/TVT.2006.873836
- N. Saberi and N. Devroye, “Geometric Programming for High-SINR Re-source Allocation in Wireless Ad-Hoc Networks,” IEEE Communications Letters, in Press.