Design Considerations and Physical Layer Performance Results for a 4G OFDMA System Employing Dynamic Subcarrier Allocation

In this paper the key design considerations and link parameters for a 4G coded OFDMA system are identified and physical layer performance results are presented for a number of transmission modes. Additionally, this paper investigates the problem of dynamic multiuser subcarrier allocation in a coded OFDMA system. A novel, near-optimal, low complexity algorithm is proposed that attempts to exploit multiuser diversity by allocating sub-carriers to users so as to achieve substantial increases in perceived channel gain which are approximately equal for all users. Performance results show that performance is significantly enhanced when this algorithm is employed. Gains up to 10 dB can be observed.