This paper proposes a new two-stage channel estimation (TSCE) method to estimate the cascaded channels in amplify-and-forward (AF) one-way relay network (OWRN) with multiple transmit and receive antennas. Different from the existing estimation methods, the proposed TSCE estimates the cascaded channel matrix by utilizing the special structure of the received signal in the destination and by exploiting the correlations among the cascaded channel matrix entries. The TSCE not only obtains the channel state information (CSI) when receiving training sequences, but also improves the accuracy of CSI when receiving the data sequences. Simulation results demonstrate that the proposed TSCE can improve estimation accuracy compared with traditional channel estimation schemes.
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