Adaptive Slot and Bit Allocation Method for OFDMA Transmission Systems

This paper proposes the orthogonal frequency division multiple access (OFDMA) transmission scheme with an adaptive slot and bit allocation method for the multi-user wireless LAN (WLAN) systems. From the fact that the radio links between different users and base station experience the independent multi-path fading, this paper proposes a priority-based adaptive slot and bit allocation method in conjunction with a swapping algorithm to assign the suitable slots and modulation methods to all users. The proposed method can achieve the higher efficient usage of frequency resource than that for the conventional fixed slot assignment with adaptive bit allocation method. This paper presents various computer simulation results to evaluate the proposed method and demonstrates that the proposed method can achieve the higher frequency resource utilization with less computation complexity and with keeping the required signal quality over the severe frequency selective fading channels