Decode-and-Forward Based Cooperative Transmission Schemes for a Relay with Multiple Receive Antennas

Performance of a decode-and-forward (DF) based two-hop multiuser cooperative transmission system is usually restricted by the link quality between a base station (BS) and a relay station (RS) as the number of users grows. Thus the BS-RS link quality should be improved to enhance the performance. In this paper, we propose two-hop cooperative communication systems with multiple receive antennas at the RS to boost the quality of the BS-RS link. With M-QAM signal constellations, our proposed optimize the system performance with a symbol error constraint. By evaluating the performance via simulations, we will show that the proposed schemes improve the performance of the DF based cooperative transmission systems significantly by exploiting advantages of multiple antennas at the RS efficiently.