Date Added: Oct 2010
Transmission schemes based on cooperative diversity, promise to increase transmission reliability by using cooperating single-antenna nodes. Examples of cooperative schemes include relaying and cooperative MIMO schemes. A key feature of cooperative diversity schemes is that the receiver of a packet is offered the opportunity to combine different copies of this packet that are obtained from different (and hopefully independent) spatial channels. In the case of classical relaying one of these copies is obtained from the direct link between transmitter and receiver, and a second copy is provided by a relay node, who captures the transmitter's packet and forwards it to the receiver.