Normalized covariance matrix quantization for MIMO broadcast systems

Inhalt:
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.