Bandwidth- and power-efficient multi-carrier multiple access

Orthogonal frequency division multiple access (OFDMA) gains increasing attention for broadband, high data rate wireless/wireline communications. In this paper, we propose a novel unitary precoded (UP) OFDMA scheme for uplink applications, which increases the system bandwidth efficiency, while preserving constant modulus transmissions. Theoretical analysis for the proposed UP-OFDMA with channel coding quantifies the performance improvement introduced by unitary precoding. It provides guidelines for practical system designs, and reveals performance gap between the proposed system and the single user bound. Simulation results confirm that the proposed system improves performance considerably relative to conventional OFDMA.