期刊名称：International Journal of Multimedia and Ubiquitous Engineering
印刷版ISSN：1975-0080
出版年度：2008
卷号：3
期号：2
出版社：SERSC
摘要：To implement transmit beamforming, which is an effective way of leveraging the diversity gains, for multiple-input single-output orthogonal frequency division multiplexing (MISOOFDM) systems, (partial) channel state information is required at the transmitter. In this paper, we present a new limited feedback scheme in MISO-OFDM systems with transmit beamforming. By dividing the total subcarriers of an OFDM symbol into a series of clusters, from the codebook we choose the “proper” one, which minimizes the average bit error rate (BER) per subcarrier of the considered cluster, as the beamforming vector for this cluster. The scheme can reduce the feedback overhead remarkably while obtain good BER performance. Further, a simple sub-optimal algorithm exploiting the correlation of channel frequency responses at different subcarriers is proposed to avoid exhaustive search in the optimal solution. The complexity analysis and simulations show that the proposed method has low computational complexity and provides improvement over the existing schemes.
