应用于MIMO-OFDMA下行链路的分组调度算法

提出了一种基于效用函数的应用于多输入多输出正交频分复用接入 (MIMO-OFDMA, Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing Access )系统下行链路的分组调度算法.该算法在调度时不仅考虑物理层的信道状况,还利用基站发送缓冲区的状态信息和用户反馈回来的ARQ(Automatic Repeat-request)信息来帮助基站做出调度决策.针对系统中多种业务的不同服务质量(QoS,Quality of Service)要求,分别设计了其效用函数,并将调度决策问题转化成一个系统总效用函数值最大化问题.同时考虑到实际的长期演进计划(LTE,Long Term Evolution) 系统中对子载波共享的限制条件,提出了一种可以降低实际复杂度的启发式算法用于求解该最优化问题.仿真结果表明,该算法不但在保证实时业务用户QoS要求方面要好于传统的调度算法,还能获得较好的系统总容量和丢包率性能.

Packet scheduling algorithm for multi-service MIMO-OFDMA downlink systems

A utility-based packet scheduling algorithm was proposed for downlink multiuser multiple input multiple output-orthogonal frequency division multiplexing access (MIMO-OFDMA) systems. The proposed algorithm not only considered the channel condition of physical layer, but also utilized the transmitting buffer status information and the automatic repeat-request (ARQ) feedback information to help improve the system performance. In order to satisfy the different qualities of service (QoS) of multi-service, different utility functions were designed for different traffics and then the scheduling problem was formulated into a problem of overall system utility maximization. Moreover, considered the limits of practical long term evolution (LTE), a heuristic algorithm with low computational complexity was proposed. The simulation results show that the proposed algorithm outperforms the existing algorithms in terms of the system throughput and the packet loss rate and can also guarantee the QoS demand of real-time traffic.