Outage-Optimal Transmit Antenna Selection for Cooperative Decode-and-Forward Systems

We propose and analyze three different transmit antenna selection schemes for cooperative diversity systems with regenerative relays. Our goal is to minimize the information outage probability by properly selecting one out of several available antenna elements at the source node. This problem is generally more involved than transmit antenna selection for conventional single-hop systems since the selection of a certain antenna element affects always both the source-to-relay as well as the source-to- destination link. The various schemes that we present are based upon different kinds of channel state information and we analyze all of them in terms of the achievable outage probability as well as the asymptotic behavior in the high SNR regime.