This paper presents a new subband allocation scheme for multiuser OFDMA systems. Adaptive OFDMA systems have focused on adapting the allocation of subcarriers and power to the instantaneous channel conditions of all users. Using frequency hopping pattern in OFDMA system allow users to minimize intercell and intracell interference, and perform frequency diversity. In contrast to conventional FH-OFDMA, which uses a channel state independent hopping sequence, the transmitter in the channel aware scheme hops to the available frequency subband which has the largest transmission gain. Simulation results demonstrate that in power constraints assumption, using our proposed channel aware frequency hopping (CAFH) along with OFDMA scheme outperforms multiuser OFDMA system with fixed subband assignment. Copyright © 2012 Praise Worthy Prize S.r.l. All rights reserved.