该文提出了一种基于服务质量(Qos)保证的次优广播/组播OFDM系统资源分配算法。算法在最优分配原则的基础上采用不同广播/组播业务目标速率作为约束条件,并以业务组中最差接收用户传输速率作为搜索目标,使得业务组中全部用户达到QoS要求,算法的公平性及有效性得到提高;同时采用时频格作为分配算法中的基本资源单位,以降低分配算法的复杂度。仿真结果表明,改进分配策略的系统吞吐量性能接近最优广播/组播分配算法,提高了广播/组播系统资源分配的公平性。
A sub-optimal resource allocation algorithm for broadcast/multicast OFDM system is presented in this paper. By proposed algorithm, the fairness and efficiency is improved based on taking the target rates of different services as Quality of Service (QoS) constraint and finding out the lowest rate in one service group for comparison in order that all users can get target QoS requirement. At the same time, the complexity of this algorithm is reduced by introduction of two-dimensional Frequency-Time Grid (FTG) scheme. Simulation results show that the efficiency of proposed allocation algorithm is obvious which has significant higher fairness and throughput being very close to the upper bound of optimum method.