Adaptive multiuser radio resource allocation for OFDMA systems

Efficient radio resource allocation is essential to provide quality-of-service (QoS) for wireless networks. In this paper, we propose an adaptive multiuser radio resource allocation model for the downlink of OFDMA system, which efficiently exploits the time diversity, frequency diversity as well as multiuser diversity in the time, frequency and user domain, respectively. According to the allocation algorithm´s computational complexity, two different-complexity adaptive resource allocation algorithms algorithm A and algorithm B - are proposed which adopt a two-step allocation method to reduce the scheduling complexity and meanwhile improve the scheduling performance. Simulation results show that while the performance of algorithm A and B is slightly different, both of the proposed algorithms yield much higher spectral efficiency and much lower outage probability, which are flexible and efficient for the downlink of OFDMA systems