Maximizing Achievable Rate Strategies for Incremental-Relay Multicarrier Transmission

This paper develops an improved amplify-and-forward (AF) orthogonal frequency-division multiplexing (OFDM) scheme, where an incremental policy is fully utilized to promote the spectrum efficiency of cooperative transmission, and presents several achievable-rate-maximizing resource allocation strategies. The high computational complexity for optimization necessitates our investigation of suboptimal approaches. However, the associated computational burdens are still intensive due to the exhaustive search nature. As a consequence, a low-complexity alternative evolves to achieve a better tradeoff between performance and complexity. Moreover, its average unconditional signal-to-noise ratio (SNR) outage probability is analytically derived. Numerical results are shown to illustrate the benefits of the proposals and verify the validity of the theoretical analysis.