Subcarrier allocation wit low-complexity in multiuser OFDM systems

In a wireless and mobile channel, a low complexity can be very important factor for an adaptive loading algorithm in orthogonal frequency division multiplexing (OFDM) systems. In this paper, we focus on how to allocate the subcarriers used in a multiuser environment to each user efficiently. First, this paper shows the shortcoming of the traditional subcarrier allocation algorithm for a multiuser OFDM system. Then, a new adaptive allocation algorithm is proposed to reduce the complexity of the allocation algorithm scheme. Consequently, in this paper it is shown that the proposed allocation algorithm has the lower computational complexity than the conventional one, while the both algorithms have almost same bit error rate (BER) performances in a Rayleigh fading environment.