Impact of CSI on Distributed Space-Time Coding in Wireless Relay Networks

We consider a two-hop wireless network where a transmitter communicates with a receiver via M relays with an amplify-and-forward (AF) protocol. Recent works have shown that sophisticated linear processing such as beamforming and distributed space-time coding (DSTC) at relays enables to improve the AF performance. However, the relative utility of these strategies depend on the available channel state information at transmitter (CSIT), which in turn depends on system parameters such as the speed of the underlying fading channel and that of training and feedback procedures. Moreover, it is of practical interest to have a single transmit scheme that handles different CSIT scenarios. This motivates us to consider a unified approach based on DSTC that potentially provides diversity gain with statistical CSIT and exploits some additional side information if available. Under individual power constraints at the relays, we optimize the amplifier power allocation such that pairwise error probabi...

• Type: Journal
• Year: 2008
• Where: CORR
• Authors: Mari Kobayashi, Xavier Mestre
• Keywords: Amplifier Power Allocation, CORR 2008, Education, Power Allocation, Relays