The paper reports on investigations into the effect of spatial correlation on channel estimation and capacity of a multiple input multiple output (MIMO) wireless communication system. Least square (LS), scaled least square (SLS) and minimum mean square error (MMSE) methods are considered for estimating channel properties of a MIMO system using training sequences. The undertaken mathematical analysis reveals that the accuracy of the scaled least square (SLS) and minimum mean square error (MMSE) channel estimation methods are determined by the sum of eigenvalues of the channel correlation matrix. It is shown that for a fixed transmitted power to noise ratio (TPNR) assumed in the training mode, a higher spatial correlation has a positive effect on the performance of SLS and MMSE estimation methods. The effect of accuracy of the estimated Channel State Information (CSI) on MIMO system capacity is illustrated by computer simulations for an uplink case in which only the mobile station (MS) transmitter is surrounded by scattering objects.
T. L. Marzetta and B. M. Hochwald, “Capacity of a mobile multiple-antenna communication link in Rayleigh flat fading,” IEEE Transactions on Information Theory, Vol. 45, No. 1, pp. 139-157, January 1999.
A. Narula, M. J. Lopez, M. D. Trott, and G. W. Wornell, “Efficient use of side information in multiple-antenna data transmission over fading channels,” IEEE Journal on Selected Areas in Communications, Vol. 16, No. 8, pp. 1423-1436, October 1998.
A. S. Kyung, R. W. Heath, and B. K. Heung, “Shannon capacity and symbol error rate of space-time block codes in MIMO Rayleigh channels with channel estimation error,” IEEE Transactions on Wireless Communication, Vol. 7, No. 1, pp. 324-333, January 2008.
X. Zhang and B. Ottersten, “Performance analysis of V- BLAST structure with channel estimation errors,” IEEE 4th Workshop on Signal Processing Advances in Wireless Communications SPAWC, pp. 487-491, June 2003.
P. Layec, P. Piantanida, R. Visoz and A. O. Berthet, “Capacity bounds for MIMO multiple access channel with imperfect channel state information,” IEEE Information Theory Workshop ITW08, pp. 21-25, May 2008.
M. Biguesh and A. B. Gershman, “MIMO channel estimation: Optimal training and tradeoffs between estimation techniques,” Proceedings of International Conference on Communications, ICC’04, Paris, France, Vol. 5, pp. 2658-2662, June 2004.
M. Biguesh and A. B. Gershman, “Training-based MIMO channel estimation: A study of estimator tradeoffs and optimal training signals,” IEEE Transactions on Signal Processing, Vol. 54, No. 3, pp. 884-893, March 2006.
X. Liu, S. Lu, M. E. Bialkowski and H. T. Hui, “MMSE Channel estimation for MIMO system with receiver equipped with a circular array antenna,” Proceedings of IEEE Microwave Conference APMC2007, pp. 1-4, De-cember 2007.
X. Liu, M. E. Bialkowski, and S. Lu, “Investigation into training-based MIMO channel estimation for spatial correlation channels,” Proceedings of IEEE International Antennas Propagation Symposium (APS-2007), pp. 51-55, August 2007.
P. F. Driessen and G. J. Foschini, “On the capacity for-mula for multiple-input multiple-output wireless channels: A geometric interpretation,” IEEE Transactions on Com-munications, Vol. 47, pp. 173-176, February 1999.
D. Shiu, G. J. Foschini, M. J. Gans, and J. M. Kahn, “Fading correlation and its effect on the capacity of mul-tielement antenna systems,” IEEE Transactions on Communications, Vol. 48, No. 3, pp. 502-513, March 2000.
P. Uthansakul, M. E. Bialkowski, S. Durrani, K. Bi- alkowski, and A. Postula, “Effect of line of sight propa-gation on capacity of an indoor MIMO system,” Pro-ceedings of IEEE International Antennas Propagation Symposium (APS-2005), Washington, DC, pp. 707-710, 2005.
T. L. Fulghum, K. J. Molnar and A. Duel-Hallen, “The Jakes fading model for antenna arrays incorporating azi-muth spread,” IEEE Transactions on Vehicular Technol-ogy, Vol. 51, No. 5, pp. 968-977, September 2002.
B. M. Hochwald and T. L. Marzetta, “Capacity of a mo-bile multiple antenna communication link in Rayleigh flat fading,” IEEE Transactions on Information Theory, Vol. 45, No. 1, pp. 139-157, January 1999.
M. Torabi, M. R. Soleymani, and S. Aissa, “On the per-formance of MIMO-OFDM systems with imperfect channel information,” International Conference on Wire-less Networks, Communications and Mobile Computing, Vol. 1, pp. 600-605, June 2005.