中文摘要：

研究了基于波束形成技术的多输入多输出无线通信系统的有效容量的问题.考虑在调制类型（M-QAM或者M-PSK）受约束的前提下,以多输入多输出波束形成技术中具有代表性的传输方案：以最大合并比传输为背景,推导了有效容量的闭合表达式.仿真结果不仅证明了性能分析的有效性,还展示了在不同天线配置下,有效容量与平均信噪比和QoS参数的关系.

英文摘要：

Effective capacity describes the rate upper bound of the communication system under the quality of service（QoS） limitation. While the foregoing performance analysis focuses mainly on the single input single output and multiple input single output systems, this paper considers the effective capacity of the multiple input multiple output（MIMO） beamforming scheme. Given that the modulation（M-QAM or M- PSK） is restricted, we investigate the representative transmission scheme of MIMO beamforming： maximal ratio combining transmission, for which the closed-form formula of effective capacity is derived. Simulation results not only demonstrate the effectiveness of our performance analysis, but also show the relationship between effective capacity and average signal-to-noise ratio as well as the relationship between effective capacity and QoS parameter for various antenna configurations.