Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Effects of Mutual Coupling and Noise Correlation on Downlink Coordinated Beamforming with Limited Feedback | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2009 Article ID 807830 10 pages doi 2009 807830 Research Article Effects of Mutual Coupling and Noise Correlation on Downlink Coordinated Beamforming with Limited Feedback Yuhan Dong Carlo P. Domizioli and Brian L. Hughes Department of Electrical and Computer Engineering North Carolina State University Raleigh NC 27695 USA Correspondence should be addressed to Yuhan Dong ydong@ Received 1 December 2008 Revised 27 March 2009 Accepted 22 April 2009 Recommended by Markus Rupp We consider the impact of receiver correlation antenna coupling matching and noise on the performance of coordinated beamforming systems. We present a new coordinated beamforming technique for two receivers that is suitable for MIMO broadcast channels with signal and noise correlation at the receiver. We then apply this technique to the specific type of signal and noise correlation that occurs in the presence of receiver mutual coupling. Numerical results suggest that even in the presence of strong coupling most of the benefits of coordinated beamforming can be preserved by using appropriate matching networks and linear beamforming. Moreover these benefits can be achieved even when feedback is limited. Copyright 2009 Yuhan Dong et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction In recent years considerable attention has been paid to multiple-input multiple-output MIMO systems which use multiple antennas at the transmitter and receiver to improve the performance of wireless communication systems over fading multipath channels 1 . In a broadcast setting when channel state information CSI is available at the transmitter linear beamforming techniques can be a simple and efficient way to communicate data from a base .