OFDMA系统保证服务质量的分组调度算法

A QoS Guaranteed Packet Scheduling Algorithm for OFDMA Systems

在正交频分多址接入系统中采用正比公平算法可以兼顾吞吐量和公平性,有效地提高系统性能。结合正比公平算法,该文提出一种应用于正交频分多址接入系统保证服务质量的分组调度算法。为防止需求速率高但瞬时信道状况差的用户分配过多的子载波,算法使用了动态变化的权重因子。在一次调度过程中,剩余子载波的权重因子可以随着子载波的分配而更新。仿真结果证明,在满足实时业务服务质量的前提下,该算法比正比公平算法具有更好的公平性。

In Orthogonal Frequency Division Multiple Access （OFDMA） systems, utilizing Proportional Fair （PF） algorithm can enhance system capacity, fairness, and performance. PF algorithm is extended, and a quality of service guaranteed packet scheduling algorithm is proposed for OFDMA systems. Users with high data rate requirements but in poor instantaneous channel state may be allocated excessive subcarriers. To prevent that situation, the algorithm uses dynamic weight factor. In a scheduling process, the weight factors of remaining subcarriers update as a subcarrier is allocated. Simulation results show that the proposed algorithm has a better performance in maintaining fairness than PF algorithm for real time services.