A new joint power and subcarrier allocation scheme for multiuser OFDM systems

In this paper, a new scheme for adaptive subcarrier bit and power allocation for downlink transmission of multiuser orthogonal frequency division multiplexing (OFDM) systems is presented. An adaptive algorithm is introduced to achieve the desired bit rate and BER for QoS (quality of service) of different users in a frequency selective fading channel, while the total transmit power is minimized. The performance and complexity of the proposed scheme is also thoroughly compared with the other existing methods. As the simulation results show, the proposed algorithm outperforms all prior sub-optimum schemes, while offering comparable computational complexity.