Resource Allocation Algorithm for Optimizing User Fairness in Multi-User OFDMA System

This paper proposed a novel resource allocation based on iterative water-filling subcarrier allocation algorithm in multi-user OFDMA system. The algorithm updated the transmit power of each subcarrier in each iterative by improve the water-filling algorithm, which could more accurately calculate the capacity of subcarrier, rather than compute the channel capacity with average power of traditional water-filling subcarrier allocation algorithm. In this paper, a power line is proposed as a reference which varies according to the allocated subcarriers. We compute the corresponding reference power line by the minimum noise-to-signal ratio first, then compare the sub-carrier to be allocated with the reference power line to use iterative water-filling, until all sub-carriers allocated. The algorithm is to solve the problem of fairness among users based on guaranteeing the total system capacity. Simulation results show that the system capacity of the system capacity close to the optimal algorithm, but greatly improves the user fairness.