分层结构分布式天线系统的性能分析  

Performance analysis of hierarchical distributed antenna systems

作　　者：蒋占军[1,2] 郑玉甫[1] 王东明[2] 王炎[2] 

机构地区：[1]兰州交通大学电子与信息工程学院,兰州730070 [2]东南大学移动通信国家重点实验室,南京210096

出　　处：《高技术通讯》2009年第9期881-886,共6页Chinese High Technology Letters

基　　金：863计划(2006AA01Z268,2007AA01Z268);国家自然科学基金(60702028)资助项目。

摘　　要：提出了一种分层结构的分布式天线系统(HDAS)。在此HDAS中,其中一个远端接入单元(RAU)以大功率发射保证对整个广义小区(GN-cell)的覆盖,而GN-cell中用户密度较大或者链路质量较差的区域配置较小功率的RAU对其进行重复覆盖。在CDMA网络环境中分析了HDAS上下行链路的信干比,其中上行链路采用基于信干比平衡准则的功率控制算法,下行链路采用RAU选择传输方案。链路性能分析表明,上行链路的信干比与GN-cell中RAU数目成正比,且与用户分布和小功率RAU的位置无关;下行链路信干比在RAU选择和RAKE接收结合时与用户分布及RAU位置基本无关。这些结论表明,CDAM HDAS可以较好地解决蜂窝移动通信系统中由于用户非均匀分布造成的扩容以及随之产生的频繁切换问题。A hierarchical distributed antenna system （HDAS） is presented. In the system, a remote access unit （RAU） covers the whole generalized cell （GN-cell） with a larger transmit power, and other RAUs serve hot-spots or poor-channel areas with smaller power in an overlaid manner. The signal to interference ratios （SIR） of both the uplink and the downlink of the HDAS are analyzed in a code division multiple access （CDMA） based network. A SIR balanced power control algorithm is used in the uplink and the RAU selection is employed in the downlink. The analysis and simulation results show that the SIR of the uplink grows with the number of RAUs in the GN-cell. And the SIRs of both the uplink and the downlink are independent of locations of RAUs with smaller power and the distribution of mobile stations in the GN-cell when the RAKE receiver is used in the downlink. The results show that the HDAS can solve the problems such as the enhancement of system capacity and frequent handoffs that are caused by the uneven distribution of users.

关 键 词：分层网络结构 分布式天线系统(DAS) 远端接入单元选择 功率控制 

分 类 号：TN820[电子电信—信息与通信工程]