A channel estimation method of multi-relay cooperative communication environment is proposed in this thesis. Considering amplify-and- forward relay (AF) protocol with orthogonal frequency division multiplexing (OFDM) transceiver, different from the traditional system model, parallel relay nodes arrangement is considered in this work. Since the decreasing effect on relay node power transmission and the interference between relays, problems on dealing with color noise and the multipath channels overlap at the destination node should be solved. The disintegrated pilot-based channel estimation is utilized to figure out the source-i’th relay (S-Ri) and i’th relay-destination (Ri-D) links respectively. Time division multiplexing (TDM) and frequency division multiplexing (FDM) based technics are introduced to the pilot arrangement at the relay node to separate the channel between different relays. The mean square error (MSE) of least squares (LS) and minimum mean square error (MMSE) channel estimation algorithms were investigated. Finally, simulation results demonstrate that the proposed methods can solve the problem on multi-relay disintegrated channel estimation.
