Transactions letters - Layered group detection for multiuser mimo wireless cdma systems

In this paper, we consider a multiuser multiple input multiple output (MIMO) CDMA system where each user is transmitting different streams spread with the same code on a set of multiple antennas. Signals from one user are received as one group and each user is thought of as a virtual group. At the receiver, group ordered successive interference cancellation detection is applied. Optimal and sub-optimal group detection orders that maximizes the system performance are then derived. Various linear group detectors are considered such as the linear decorrelators and a closed form expression of the optimal order is given for the case of each of these group detectors. Numerical results demonstrate significant gains in the system performance as well as the importance of group ordering