前的資源配置演算法研究工作通常都會假設可以獲得完美的通道資訊，不幸的是，由於通道偵測誤差和時間回報延遲等原因，使得獲得完美的通道資訊在實際系統上是不可行的，因此在不完全通道資訊下的演算法獲得了很大的注意力。在本文中，我們就多輸入多輸出正交分頻多工系統下鏈方向提出了子載波、位元和功率分配演算法，我們使用一種含有2維編碼器-波束形成器的傳輸器以動態多使用者的多輸入多輸出正交分頻多工傳輸技術完成此配置，在假設基地台知道所有使用者所有子載波部分資訊，提出的配置演算法目的在使傳送的功率最小化，同時需要滿足傳送時的錯誤率限制及每個使用者的傳輸速度限制條件，而在模擬結果，我們可以看出我們提出的演算法在傳送功率上有著比傳統演算法更高的效能，並且有較低的複雜度。

Previous research works in the design of resource allocation algorithms have typically assumed the availability of perfect channel state information (CSI). Unfortunately, this is unpractical due to channel estimation error and channel feedback delay. Hence, the algorithm based on partial CSI draws much more attention. In this paper, we develop a subcarrier, bit, and power allocation algorithm for MIMO OFDM-based multiuser communication systems on downlink. We exploit a dynamic multiuser MIMO-OFDM transmit scheme with two-dimensional (2-D) coder-beamformers to the transmitter. Assuming that base stations know the partial CSI of all subcarriers of all users, the proposed allocation algorithm intends to minimize the overall transmit power while satisfying required error performance under a constraint of transmission rate of each user. The proposed algorithm offers better performance in terms of transmit power than the conventional algorithm as illustrated in the simulation results. The computational complexity is reduced.

[1] I. Kim, I.-S. Park, and Y. H. Lee, “Use of linear programming for dynamic subcarrier and bit allocation in multiuser OFDM,” IEEE Trans. Veh. Technol., vol. 55, no. 4, pp. 1195-1207, Jul. 2006.
[2] C. Y. Wong, R. S. Cheng, K. B. Letaief, and R. D. Murch, “Multicarrier OFDM with adaptive subcarrier, bit, and power allocation,” IEEE J. Sel. Areas Commun., vol. 17, no. 10, pp. 1747-1758, Oct. 1999
[3] I. C. Wong and B. L. Evans, “Adaptive downlink OFDMA resource allocation” in Proc. Asilomar Conf. Signals, Syst. and Comput., no.10, pp.2203-2207, Oct. 2008.
[4] I. C. Wong and B. L. Evans, “Optimal resource allocation in the OFDMA downlink with imperfect channel knowledge”, IEEE Trans. Commun., vol. 57, no. 1, pp.232-241, Jan. 2009.
[5] D. Kivanc, G. Li and H. Liu, “Computationally efficient bandwidth allocation and power control for OFDMA”, in IEEE Trans. Wireless Commun., vol. 2, no.11, pp. 1150-1158, Nov. 2003.
[6] A. J. Goldsmith and S. G. Chua, “Variable-rate variable-power MQAM for fading channels,” IEEE Trans. Commun., vol. 45, no. 10, pp. 1218–1230, Oct. 1997.
[7] J. G. Proakis and M. Salehi, Digital Communications. New York: McGrawHill, 5th Edition, 2008.
[8] E. G. Larsson and P. Stoica, Space-Time Block Coding for Wireless Communications, Cambridge University Press, Cambridge, UK, 2003
[9] S. M. Alamouti, “A simple transmit diversity technique for wireless communication,” IEEE J. Sel. Areas Commun., vol. 16, no.10 , pp. 1451-1458, Oct. 1998.
[10] G. Jöngren, M. Skoglund, and B. Ottersten, “Combining beamforming and orthogonal space–time block coding,” IEEE Trans. Info. Theory, vol. 48, no. 3, pp. 611-627, Mar. 2002.
[11] S. Zhou and G. B. Giannakis, “Optimal transmitter eigen-beamforming and space-time block coding based on channel mean feedback,” IEEE Trans. Signal Processing, vol. 50, pp. 2599–2613, Oct. 2002.
[12] M. Lin, M. Li, L. Yang, and X. You, “Adaptive transmit beamforming with space-time block coding for correlated MIMO fading channels,” in Proc. IEEE Int. Conf. Commun., no.6, pp. 5879-5884, Jun. 2007.
[13] R. Chen, J. G. Andrews, and R. W. Heath, “ Multiuser space-time block coded MIMO system with downlink precoding ,” in Proc. IEEE Int. Conf. Commun., vol.5, no.6, pp. 2689-2693, Jun. 2004.
[14] P. Xia, S. Zhou, and G. B. Giannakis, “Adaptive MIMO-OFDM based on partial channel state information” IEEE Trans. Signal Processing, vol. 52, No. 1, pp. 202 – 213, Jan. 2004.
[15] Z. Hu, G. Zhu, Y. Xia, and G. Liu, “Multiuser subcarrier and bit allocation for MIMO-OFDM systems with perfect and partial channel information,” in Proc. Wireless Commun. and Networking Conf., vol. 2, no. 5, pp. 1188 – 1193, Mar. 2004.
[16] R. Chemaly, K. B. Letaief, and D. Zeghlache, “Adaptive resource allocation for multiuser MIMO/OFDM networks based on partial channel state information,” in Proc. IEEE Global Telecommun. Conf., vol. 6, no. 12, pp.3921-3926 , Dec. 2005.
[17] W. L. Ho and Y. C. Liang, “Optimal resource allocation for multiuser MIMO-OFDM systems with user rate constraints,” IEEE Trans. Veh. Technol., vol. 58, no. 5, pp.1190-1203, Mar. 2009.
[18] Y. I. Shin, T. S. Kang, and H. M. Kim, “An efficient resource allocation for multiuser MIMO-OFDM systems with zero-forcing beamformer,” IEEE Int. Symp. Personal, Indoor and Mobile Radio Commun. , no. 9, pp.1-5, Sept. 2007.
[19] Y. H. Zeng, P. Shang, G. X. Zhu, and W. M. Wu, “Multiuser scheduling with orthogonal space-division multiplexing,” in Proc. Wireless Commun., Networking and Mobile Comput., no. 9, pp.1-4, Sept. 2010.
[20] K. Gunaseelan, P. Reba, and A. Kandaswamy, “Adaptive resource allocation with multiuser interference cancellation for MIMO OFDM systems,” IEEE Int. Conf. Signal Processing Syst., no.5, pp.239-243, May. 2009.
[21] V. D. Papoutsis, I. G. Fraimis, and S. A. Kotsopoulos, “User selection and resource allocation algorithm with fairness in MISO-OFDMA,” IEEE Commun. Lett., vol. 14, no. 5, pp.411-413, May 2010.
[22] M. Katoozian, K. Navaie, and H. Yanikomeroglu, “Utility-based adaptive radio resource allocation in OFDM wireless networks with traffic prioritization,” IEEE Trans. Wireless Commun., vol. 8, no. 1, pp.66-71, Jan. 2009.
[23] V. K. N. Lau, “Adaptive resource allocation for multiuser MIMO systems with transmit group MMSE,” IEEE Trans. Wireless Commun., vol. 8, no. 5, pp.2362-2368, May. 2009.
[24] M. T. Ivrlac, W. Utschick, and J. A. Nossek, “Fading correlations in wireless MIMO communication systems,” IEEE J. Sel. Areas Commun., vol. 21, no. 5, pp.819-828, Jun. 2003.
[25] W. C. Jakes, Microwave Mobile Communication. Piscataway, NJ: IEEE Presss, 1994.
[26] L. Dong, G. Xu, and H. Ling, “Prediction of fast fading mobile radio channels in wideband communication systems,” in Proc. IEEE Global Telecommun. Conf., vol. 6, no.11, pp. 3287-3291, Nov. 2001.
[27] S. K. Lai, R. S. Cheng, K. B. Letaief, and C. Y. Tsui, “Adaptive tracking of optimal bit and power allocation for OFDM systems in time-varying channels,” in Proc. Wireless Commun. and Networking Conf., vol. 2, no.2, pp. 776–780, Sept. 1999.
[28] J. C. Lin, “Least-squares channel estimation for mobile OFDM communication on time-varying frequency-selective fading channels,” IEEE Trans. Veh. Technol., vol. 57, no. 6, pp. 3538-3550, Nov. 2008.
[29] M. Abramowitz and I. A. Stegun, Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 10th ed. U.S. Govt. Print. Off., 1972.