Superimposed Training Based Channel Estimation for OFDM Modulated AF Relay Networks
Research on two-hop relay networks has attracted much attention since the pioneer work. Most of these works require perfect channel estimates at both the relay nodes and the destination nodes. In order to obtain the accurate Channel State Information (CSI), studies on the optimal channel estimation were reported recently. The optimal Maximum Likelihood (ML) estimators and Linear Minimum Mean Square Error (LMMSE) estimator for Decode-and-Forward (DF) relay network has been proposed. A counterpart work was made, where the channel estimation for STC based Amplify-and-Forward (AF) relay network was studied.