Resource allocation and subcarrier pairing in energy efficient relay-assisted OFDMA downlink systems

Abstract

The energy efficiency (EE) maximization problem in amplify-and-forward (AF) relay-assisted downlink channels with orthogonal frequency-division multiple access (OFDMA) is studied. The power allocation is optimized together with subcarrier allocation and pairing at the relay. As the base station and the relay have individual power constraints, an alternating optimization approach is adopted to solve the problem. Numerical results show that the proposed algorithm outperforms other benchmark schemes in terms of EE.