Optimal subcarrier assignment for single cell multiuser OFDM system

Multiuser OFDM system can achieve large channel capacity due to large user diversity gain. The large peak to average power (PAPR) of OFDM signal, however, reduces transmit power of base station. As a result, the number of supportable users becomes smaller and thus user diversity gain becomes small. Our considered subcarrier assignment technique can reduce the PAPR as advantage but reduce user diversity gain as disadvantage. Since the transmitted power becomes larger due to PAPR reduction, the number of supportable users becomes large and then the user diversity gain is enhanced. Therefore, the disadvantage of our considered technique can be compensated for cell environment and thus the optimal subcarrier assignment can be constructed. In this paper, we clarify the optimal construction of subcarrier assignment for largest channel capacity.