Error-Rate Performance Analysis of Cooperative OFDMA System With Decode-and-Forward Relaying

In this paper, we investigate the performance of a cooperative orthogonal frequency-division multiple-access (OFDMA) system with decode-and-forward (DaF) relaying. Specifically, we derive a closed-form approximate symbol-error-rate expression and analyze the achievable diversity orders. Depending on the relay location, a diversity order up to (L(S_kD) + 1) + Σ_m=1^M min(L(S_kR_m) + 1, L(R_mD) + 1) is available, where M is the number of relays, and L(S_kD) + 1, L(S_kR_m) + 1, and L(R_mD) + 1 are the lengths of channel impulse responses of source-to-destination, source-to-mth relay, and mth relay-to-destination links, respectively. Monte Carlo simulation results are also presented to confirm the analytical findings.