Layered transmit diversity for quasi-static wireless channels

We analyze space-time block codes for transmit diversity utilization from a signal processing viewpoint. The study shows that space-time block codes are not able to efficiently exploit all available signal space dimensions. In particular, the rate limitation of space-time block codes incurs a large capacity penalty. We propose a novel signal processing technique, layered transmit diversity, which achieves full rate transmission. The technique combines interference cancellation processing in the Bell Laboratory Layered Space-Time (BLAST) architecture and space-time block coding to jointly process real and imaginary parts of received signals. it is shown that layered transmit diversity can approach channel capacity.