On the Optimal System Configurations of Two-Hop Relay Network

Fixed relay, which has been taken into consideration for beyond-3G cellular networks, is a promising technique to provide high data rate coverage in a cost-effective manner. In this paper, we study the capacity and optimal configurations of two-hop relay downlink system. First, we summarize two typical resource allocation schemes of the two hops on the assumption of TDD system-one is in time domain and the other is in frequency domain. Next, according to the improved evaluation model, we demonstrate that it is critical to improve the capacity of the BS to RS link to achieve higher system throughput. Then, different relay station (RS) positions are discussed in terms of the system throughput. The evaluation results are provided to show the optimal deployment of RS. Finally, we present that the ratio between the transmit power of base station (BS) and that of RS influences the throughput greatly. We have got the conclusion that resource allocation in time domain is better than in frequency domain in respective of throughput.