User Set Estimation for Adaptive Resource Allocation in a Multiuser-OFDM System

In the multiuser OFDM system, various adaptive subcarrier-bit-and-power allocation algorithms have been investigated based on the assumption that the number of supportable users is given. This paper proposes a supportable user set estimation in order to adopt those allocation algorithms in the multiuser-OFDM system. The number of supportable users is estimated in an iterative way by calculating the required power approximately and comparing it with an available power after determining the number of subcarriers to be allocated. Simulation results show that the proposed user set estimation provides a significant complexity reduction for the adaptive subcarrier-bit-and-power allocation in the multiuser-OFDM system.