Capacity/Throughput Optimization for H-BLAST with SC Receiver over MIMO Channels

Among various Bell Labs layered space-time (BLAST) architectures over multiple input multiple output (MIMO) channels, we focus on the horizontal BLAST (H- BLAST) transmission scheme as it can achieve the channel capacity with a simple receiver, namely the successive cancellation (SC) receiver. The power optimization across layers is considered with a short-term power constraint. In addition, for block- fading channels, the rate optimization across layers is studied to maximize the throughput when the instantaneous channel state information (CSI) is not available. Since the CSI is not available, the rates can be greater than the instantaneous channel capacity and error propagation in the SC receiver is inevitable. Thus, the rate optimization plays a key role in reducing the chance of error propagation to maximize the throughput. It is shown that the optimal rates can be obtained recursively and each optimization can be carried out by a one-dimensional search.