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.