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báo cáo hóa học:" Research Article Progressive Refinement of Beamforming Vectors for High-Resolution Limited Feedback"

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 Progressive Refinement of Beamforming Vectors for High-Resolution Limited Feedback | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2009 Article ID 463823 13 pages doi 10.1155 2009 463823 Research Article Progressive Refinement of Beamforming Vectors for High-Resolution Limited Feedback Robert W. Heath Jr. 1 Tao Wu 2 and Anthony C. K. Soong3 1 Wireless Networking and Communications Group Department of Electrical and Computer Engineering The University of Texas at Austin 1 University Station C0803 Austin TX 78712-0240 USA 2Huawei Technologies 10180 Telesis Court Suite 365 San Diego CA 92121 USA 3Huawei Technologies 1700 Alma Drive Suite 500 Plano TX 75075 USA Correspondence should be addressed to Robert W. Heath Jr. rheath@ece.utexas.edu Received 25 December 2008 Revised 20 April 2009 Accepted 15 June 2009 Recommended by Ana Perez-Neira Limited feedback enables the practical use of channel state information in multiuser multiple-input multiple-output MIMO wireless communication systems. Using the limited feedback concept channel state information at the receiver is quantized by choosing a representative element from a codebook known to both the receiver and transmitter. Unfortunately achieving the high resolution required with multiuser MIMO communication is challenging due to the large number of codebook entries required. This paper proposes to use a progressively scaled local codebook to enable high resolution quantization and reconstruction for multiuser MIMO with zero-forcing precoding. Several local codebook designs are proposed including one based on a ring and one based on mutually unbiased bases both facilitate efficient implementation. Structure in the local codebooks is used to reduce search complexity in the progressive refinement algorithm. Simulation results illustrate sum rate performance as a function of the number of refinements. Copyright 2009 Robert W. Heath Jr. et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use .