Outage analysis of blind cooperative diversity

Mobile users with single antennas can still take advantage of spatial diversity through cooperative space-time encoded transmission. In this paper, we consider a scheme in which a relay chooses to cooperate only if its source-relay channel is of an acceptable quality and we evaluate the usefulness of relaying when the source acts blindly and ignores the decision of the relays whether they may cooperate or not. In our study, we consider regenerative relays in which the decisions to cooperate are based on a targeted end-to-end data rate R. We derive the end-to-end outage probability for a transmission rate R and a code rate rho, and look at a power allocation strategy between the source and the relays in order to minimize the end-to-end outage probability at the destination for high SNR. Some selected performance results show that computer simulations based results coincide with our analytical results.