分布式多天线技术研究

摘要

在基于多输入多输出-正交频分复用(MIMO-OFDM)技术的下一代宽频无线通信系统中,为了提高频谱利用率,一般采用同频组网,这就在小区边缘引入了同频干扰,影响了系统覆盖范围、容量以及边缘用户的切换体验.分布式多天线系统可以有效地解决上述问题,它通过拉远天线的距离,充分利用多输入多输出(MIMO)技术的空间分集和宏分集优势,通过集中式的预编码、用户调度、功率控制等策略较好地控制基站内不同小区间的干扰,尤其适合于增强数据热点地区的覆盖,减少用户的切换次数,提升小区边缘用户的服务质量.%Multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) is the key technology for next-generation wireless communication systems. To improve spectral efficiency, base stations use the same frequency band, which causes co-channel interference, reduces coverage area and system throughput, and weakens handover performance for cell-edge users. To overcome these problems, distributed antenna system (DAS) is employed. DAS can make full use of the space diversity and macro diversity of MIMO technology by dividing antennas into several independent sets and locating them in different geographic positions. Moreover, mutual interference between neighbor cells can be controlled by centralized precoding, joint scheduling, power control, and other advanced technologies. DAS is especially useful for enhancing the coverage of hotspots, decreasing unnecessary handover, and increasing QoS for cell-edge users.