Capacity analysis of subcarrier pairing for OFDMA-based DF relay link over Rayleigh channel

In this paper we analyze the end-to-end capacity of subcarrier pairing strageties of OFDMA-base DF relay link over rayleigh fading channels. We compare fixed pairing strategy to optimal pairing strategy in the circumstance that the relay is fixed or mobile.The main contribution of this paper is deriving the closed-form expressions for average end-to-end SNR and capacity in these circumstances. The simulation result illustrates that the optimal pairing scheme can bring performance gain over fixed subcarrier pairing as expected.