Optimal space‐time scheduling for block fading channels with partial power feedbacks

The multi‐user multiple‐input‐multiple‐output (MIMO) space–time scheduling problem is the prime focus of the paper. Using multiple transmit (nT) and receive antennas (nR), it is well known that the link‐level throughput will be increased linearly with respect to min[nT, nR] without increasing the bandwidth and power budget. However, optimizing the link‐level performance of the MIMO system does not always imply achieving scheduling‐level optimization. Therefore, the design optimization across the link layer and the scheduling layer is very important to fully exploit the temporal and spatial dimensions of the communication channel. In this paper, we address the design of the optimal space–time scheduler for the multi‐user MIMO system based on an information theoretical approach. Since full knowledge of channel matrix at the transmitter requires a feedback channel capacity not scalable with respect to nT (number of transmit antennas at mobiles) and nR (number of receive antennas at base station), we will assume two partial feedback models. © 2003 Lucent Technologies Inc.