Eigen-mode transmission for jointly correlated MIMO broadcast channels

In this paper, we investigate the ergodic sum rate and present low complexity transceiver designs for the multiple-input multiple-output (MIMO) broadcast channels (BC) under jointly correlated fading. We assume that each user has perfect channel state information (CSI), while the base station only has access to each user´s statistical CSI. Eigen-mode space division multiple access transmission is derived through the maximization of the sum rate. We also derive new closed-form upper bounds on the sum rate of the eigen-mode transmission system. Based on these upper bounds and the property of matrix permanent, we propose two eigen-mode power allocation algorithms which are shown to perform well and require the base station only to have the statistical CSI of each user.