A New Resource Allocation Scheme for Downlink OFDM Systems

Abstract

In this paper, we consider the problem of subcarrier allocation in OFDM systems. As we know, for single-user OFDM systems, some algorithms can be used to find the resource allocation that minimizes the total transmit power. In the multiuser OFDM systems, however, the subcarrier allocation is much more complex. In our paper, we suggest an algorithm which adopts a new assignment strategy. Firstly, we separate all the subcarriers into several resource blocks, then, we use some single user allocation algorithms to allocate non-conflicted blocks to multiple users. Finally, according to the principle of power minimization, we try to resolve the conflict problem coming from the situation that a block may be assigned to some users at the same time. Simulation results indicate that the performance of our algorithm is better than that of the optional allocation while the complexity is reduced