An optimal bit loading algorithm in multicell multiuser OFDM systems

Multicarrier modulation techniques are being investigated and adopted for many wireless applications that aim to provide broadband transmission capabilities with a good performance in multipath environment. Currently, many optimal and suboptimal subcarrier, bit, power loading algorithms have been developed in multiuser and single-cell OFDM systems and verified to outperform other multiuser techniques. In this paper, we put the OFDM techniques into cellular environment --- multicell environment. Since a cellular system use frequency reuse concept to enhance the efficiency of spectral utilization, it introduces cochannel interference. In this paper, we analyze the performance of multicell OFDM system in the presence of cochannel interference, and propose a dynamic subcarrier allocation and bit loading algorithm in a multiuser and multicell OFDM-TDMA system to maximize the system throughput, mitigate the effect of CCI and satisfy the required quality of service. The simulation results show that the proposed algorithm is more efficient than the equal power allocation algorithms.