Space-time block coded amplify-and-forward cooperative relay without channel state information at relay station

In this paper, we propose a space-time block coded (STBC) amplify-and-forward cooperative (STBC-Co-AF) relay which requires no knowledge of CSI at relay station (RS). In STBC-Co-AF relay, the source node transmits 2-block signal to both RS and the destination node in the first time slot and then, RS transmits amplified STBC-coded signal to the destination node in the second time slot. The destination node performs a series of frequency-domain equalization (FDE), diversity combining, and STBC decoding by viewing the concatenation of the channels between the source node-RS link and between the RS-destination node link as an equivalent channel. We evaluate, by computer simulation, the average bit error rate (BER) performance when using STBC-Co-AF relay and show that the STBC-Co-AF relay can achieves the BER performance superior to Co-AF relay.