Adaptive joint subchannel and power allocation for multi-user MIMO-OFDM systems

In this paper, we investigate the resource allocation issue in spatial-multiplexing based downlink multiuser multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. The key issue is the allocation of subchannels and power among users to share the system. Previous literature mainly focus on maximizing capacity but ignore the intrinsic coverage shrinkage problem in a MIMO system. Particularly, we formulate a system with larger coverage and link reliability under a proportional rate requirement among users. To alleviate the complexity of jointly optimal subchannel and power allocation, we at first propose two suboptimal subchannel allocation algorithms, namely, user-oriented and subchannel-oriented allocations. We next propose a low-complexity power allocation method.

[1]  Edwin K. P. Chong,et al.  An Introduction to Optimization: Chong/An Introduction , 2008 .

[2]  Hui Liu,et al.  An efficient multiuser loading algorithm for OFDM-based broadband wireless systems , 2000, Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137).

[3]  M. J. Gans,et al.  On Limits of Wireless Communications in a Fading Environment when Using Multiple Antennas , 1998, Wirel. Pers. Commun..

[4]  Chiung-Jang Chen,et al.  Enhancing coverage and capacity for multiuser MIMO systems by utilizing scheduling , 2006, IEEE Transactions on Wireless Communications.

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

[6]  John M. Cioffi,et al.  Increase in capacity of multiuser OFDM system using dynamic subchannel allocation , 2000, VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026).

[7]  B.L. Evans,et al.  A low complexity algorithm for proportional resource allocation in OFDMA systems , 2004, IEEE Workshop onSignal Processing Systems, 2004. SIPS 2004..

[8]  Khaled Ben Letaief,et al.  An efficient resource-allocation scheme for spatial multiuser access in MIMO/OFDM systems , 2005, IEEE Transactions on Communications.

[9]  Emre Telatar,et al.  Capacity of Multi-antenna Gaussian Channels , 1999, Eur. Trans. Telecommun..

[10]  O. Nelles,et al.  An Introduction to Optimization , 1996, IEEE Antennas and Propagation Magazine.

[11]  Jeffrey G. Andrews,et al.  Adaptive resource allocation in multiuser OFDM systems with proportional rate constraints , 2005, IEEE Transactions on Wireless Communications.

[12]  G. Li,et al.  On the optimality of downlink OFDMA MIMO systems , 2004, Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004..

[13]  Larry J. Greenstein,et al.  Some results and insights on the performance gains of MIMO systems , 2003, IEEE J. Sel. Areas Commun..

[14]  D.J. Love,et al.  WLC42-2: Spatial Multiplexing with Opportunistic Scheduling for Multiuser MIMO-OFDM Systems , 2006, IEEE Globecom 2006.