Energy-Efficient Subcarrier-and-Bit Allocation in Multi-User OFDMA Systems

Energy efficiency is becoming increasingly important for wireless communication systems in order to minimize carbon footprint of wireless networks and to increase the battery life of mobile terminals. The spectral-energy efficiency trade-off is of primary significance to determine how much energy per bit is required in a wireless communication system to achieve a specific spectral efficiency. In this paper, we study energy-efficient resource allocation scheme for Orthogonal Frequency- Division Multiple Access (OFDMA) systems with multiple users. The trade-off between spectral and energy efficiencies is analyzed under the constraint of maintaining the fairness among users. We first formulate the energy-efficient optimization problem as an integer fractional programming. We then apply an iterative fractional method to simplify the problem to integer linear programming (ILP) problem. Simulation results demonstrate that the impact of user's quality of service (QoS) is minor on the energy efficiency when a large spectral efficiency is required.

[1]  Khaled Ben Letaief,et al.  Multiuser OFDM with adaptive subcarrier, bit, and power allocation , 1999, IEEE J. Sel. Areas Commun..

[2]  Babak Daneshrad,et al.  An Energy-Efficient Water-Filling Algorithm for OFDM Systems , 2010, 2010 IEEE International Conference on Communications.

[3]  Gerhard Fettweis,et al.  Energy-Efficient Multi-Carrier Link Adaptation with Sum Rate-Dependent Circuit Power , 2010, 2010 IEEE Global Telecommunications Conference GLOBECOM 2010.

[4]  Geoffrey Ye Li,et al.  Energy Efficient Design in Wireless OFDMA , 2008, 2008 IEEE International Conference on Communications.

[5]  Kwang Bok Lee,et al.  Transmit power adaptation for multiuser OFDM systems , 2003, IEEE J. Sel. Areas Commun..

[6]  Geoffrey Ye Li,et al.  Energy-Efficient Transmission in Frequency-Selective Channels , 2008, IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference.

[7]  Werner Dinkelbach.  On Nonlinear Fractional Programming , 1967 .

[8]  Erik B. Bajalinov,et al.  Linear-Fractional Programming Theory, Methods, Applications and Software , 2013 .

[9]  Lajos Hanzo,et al.  Green radio: radio techniques to enable energy-efficient wireless networks , 2011, IEEE Communications Magazine.

[10]  Tomás̆ Novosad,et al.  Radio Network Planning and Optimisation for Umts , 2006 .

[11]  Geoffrey Ye Li,et al.  Low-Complexity Energy-Efficient OFDMA , 2009, 2009 IEEE International Conference on Communications.

[12]  Cheng-Xiang Wang,et al.  Spectral-energy efficiency tradeoff in Cognitive Radio networks with peak interference power constraints , 2011, 2011 IEEE 13th International Conference on Communication Technology.

[13]  M. Cetron,et al.  Energy efficiency enhancements in radio access networks , 2004 .

[14]  Muhammad Ali Imran,et al.  Cellular Energy Efficiency Evaluation Framework , 2011, 2011 IEEE 73rd Vehicular Technology Conference (VTC Spring).

[15]  Xianmin Wang,et al.  Efficient optimal and suboptimal radio resource allocation in OFDMA system , 2008, IEEE Transactions on Wireless Communications.

[16]  Cong Xiong,et al.  Energy- and Spectral-Efficiency Tradeoff in Downlink OFDMA Networks , 2011, IEEE Transactions on Wireless Communications.

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

[18]  Yong Hoon Lee,et al.  Use of linear programming for dynamic subcarrier and bit allocation in multiuser OFDM , 2006, IEEE Transactions on Vehicular Technology.

[19]  Tao Chen,et al.  Energy efficiency metrics for green wireless communications , 2010, 2010 International Conference on Wireless Communications & Signal Processing (WCSP).

[20]  Geoffrey Ye Li,et al.  Interference-Aware Energy-Efficient Power Optimization , 2009, 2009 IEEE International Conference on Communications.