User Selection Criteria for Uplink Spatial Multiplexing MIMO Systems
- 121 Downloads
We study in this paper multiuser uplink scheduling algorithms for Multiple-Input Multiple-Output (MIMO) systems, where the multiusers compete for the MIMO Channel and the scheduler selects one user at a time based on a certain criterion. Then the selected user spatially multiplexes his data over the transmit antennas. This spatial multiplexing (SM) scheme provides high data rates while the multiuser diversity obtained from scheduling improves the performance of the uplink system. At the receiver, the Vertical-Bell-Labs LAyered Space Time architecture (V-BLAST) is used to detect the information layers. The main contribution of this paper is proposing and comparing the performance of several scheduling criteria for MIMO uplink scheduling. In addition, novel V-BLAST capacity bounds based on random matrix theory is presented. Furthermore, we investigate suboptimal schedulers and compare their performance. The main results of this study show that the scheduler that maximizes the optimal MIMO capacity doesn’t work well for a V-BLAST system. Instead, the optimal scheduler that maximizes the V-BLAST capacity is derived and analyzed. In addition, we look into scheduling for SM with sphere decoding and we find that in this case, using MIMO capacity as the scheduling criterion performs the best.
KeywordsMIMO multiuser uplink scheduling VBLAST Capacity Spatial multiplexing
The author would like to acknowledge the support provided by King Fahd University of Petroleum and Minerals (KFUPM) and King Abdulaziz City for Science and Technology (KACST) for funding this work through project number AR-29-79.
- 1.Knopp, R., & Humblet, P. (1995). Information capacity and power control in single cell multiuser communications. In Proceedings of the IEEE international computer conference (ICC’95), Seattle, WA.Google Scholar
- 2.Tse, D. N. C. (1997). Optimal power allocation over parallel Gaussian channels. In Proceedings of international symposium on information theory. Ulm, Germany.Google Scholar
- 3.Heath, Jr., R. W., Airy, M., & Paulraj, A. J. (2001). Multiuser diversity for MIMO wireless systems with linear receivers. In Signal, systems and computers 2001, conference record of the thirty-fifth asilomar conference on, vol. 2, pp. 1194–1199.Google Scholar
- 4.Airy, M., Shakkattai, S., & Heath, Jr., R. W. (2003). Spatially greedy scheduling in multi-user MIMO wireless systems. In Signals, systems and computers, 2003. Conference record of the thirty-seventh asilomar conference on, vol. 1, pp. 982–986.Google Scholar
- 6.Pan, C.-H., & Lee, T.-S. (2013). Efficient QR-based multi-mode precoding for limited feedback multi-user MIMO systems. Wireless Personal Communications, Published Online, pp. 1–19.Google Scholar
- 8.Lau, V.K.N., Liu, Y., & Chen, T.A. (2002). Optimal multi-user space time scheduling for wireless communications. In IEEE 56th VTC 2002-Fall. (2002), vol. 4, pp. 1939–1942.Google Scholar
- 9.Al-Ghadhban, S., Buehrer, R. M., & Robert, M. (2007). Uplink scheduling criteria comparison for V-BLAST users. In 9th international symposium on signal processing and its applications, 2007, pp. 1–4.Google Scholar
- 10.Wolniansky, P. W., Foschini, G. J., Golden, G. D., & Valenzuela, R. A. (1998). V-BLAST: An architecture for realizing very high data rates over the rich-scattering wireless channel. In Proceedings of ISSSE-98, Pisa, Italy, pp. 295–300.Google Scholar
- 16.Loyka, S., & Gagnon, F. (2004). On BER analysis of the BLAST without optimal ordering over Rayleigh fading channel. In Vehicular technology conference, VTC2004-Fall, IEEE 60th, vol. 2, pp. 1473–1477.Google Scholar
- 17.Jiang, Y., Zheng, X., & Li, J. (2005). Asymptotic performance analysis of V-BLAST. In Global telecommunications conference, 2005. GLOBECOM ’05. IEEE, vol. 6, p. 3886.Google Scholar
- 18.Lee, H., & Lee, I. (2006). Channel capacity of BLAST based on the zero forcing criterion. In Vehicular technology conference, VTC 2006-Spring. IEEE 63rd, vol. 4, pp. 1615–1619.Google Scholar