Résumé: Resource allocation in multiuser OFDM systems is a complex nonlinear optimization problem. In order to avoid direct solution, based on the analytical results of the problem of minimizing the total transmit power, a two-step subcarrier allocation algorithm is presented. The algorithm reduces the total transmit power by reducing the achievable minimum transmit power value required by each user. Subcarriers are allocated in the algorithm according to the data rate required by users and the channel characteristics. The required number of subcarriers allocated to users does not need to be known in advance. The allocation process consists of two steps: basic subcarrier allocation and residual subcarrier allocation. Numerical results demonstrate that the proposed algorithm can reduce the total transmit power effectively.

Langue: Anglais