Recent results on coding for multiple-antenna transmission systems

We describe recent results on multiple-antenna transmission systems. These are known to offer a potential performance, in terms of bit/s/Hz, that cannot be obtained otherwise with present-day technology. We summarize recent results showing the theoretical performance limits of these systems under the assumptions that the channel gains are known to the receiver, to the transmitter and to the receiver, or to neither. The design of coding schemes that approach these limits is also addressed