Normalized covariance matrix quantization for MIMO broadcast systems

Conference: European Wireless 2011 - Sustainable Wireless Technologies
04/27/2011 - 04/29/2011 at Vienna, Austria

Proceedings: European Wireless 2011

Pages: 6Language: englishTyp: PDF

Personal VDE Members are entitled to a 10% discount on this title

Authors:
Schober, Karol; Määttänen, Helka-Liina; Tirkkonen, Olav; Wichman, Risto (Aalto University School of Science and Technology, PO Box 13000, FI-00076 AALTO, Helsinki, Finland)

Abstract:
We propose Eigen quantization as an alternative to normalized channel covariance matrix Direct quantization. The normalized covariance matrix is decomposed into the eigenspace and the eigenvalues that are quantized separately. We provide theoretical cumulative density function of normalized ordered eigenvalues for case of two eigenvalues. In addition, we propose an improved method of cumulative density function (CDF) quantization. We show that with Generalized Eigenvector (GE) precoding and Nt = Nr = 2, Improved Direct quantization performs slightly better than Eigen quantization. Contrary, when Nt = 4,Nr = 2 Eigen quantization is superior.