下行链路基站协同蜂窝系统中不完全同步下的干扰消除方法  

Interference mitigation schemes for cellular system with downlink base station cooperation under imperfect synchronization

作　　者：艾婷[1] 武卓[1] 

机构地区：[1]上海大学通信与信息工程学院,上海200072

出　　处：《电子测量技术》2013年第3期1-8,共8页Electronic Measurement Technology

摘　　要：多蜂窝联合处理可以消除蜂窝间干扰,提高蜂窝系统的频谱效率。但是,对多蜂窝联合处理的研究还多局限在假设多个协同基站的信号同步到达接收端的场景。针对一个下行链路基站协同不完全同步的蜂窝系统,提出了一种使用1bit反馈预编码和信道衰落补偿功率分配的内部联合分布式空时编码基站协同方案,用以消除蜂窝边缘用户遭受到的蜂窝间干扰以及协同基站不同步引起的码间干扰。仿真结果表明,该方法可以明显的消除蜂窝边缘用户所遭受到的蜂窝间干扰和码间干扰,明显提高系统的误码率性能;与基站间不协同传输、即基站间以时分多址的方式传输信号时相比,可以提高系统的分集增益和频谱效率,同时保持一个相对低的结构和计算复杂度。Multi-cell joint processing can mitigate inter-ceU interference and thereby increase the spectral efficiency of cellular systems greatly. However, most research on multi-ceil joint processing has assumed that cooperative base stations （BS） are perfectly synchronized. Considering the difficulty in meeting such an assumption in many practical systems which will cause inter-symbol interference（ISI） from neighboring symbols at the US,in this paper,we propose a BS cooperation transmission scheme on the downIink under imperfect synchronization, namely inner joint-distributed space-time coding （IN-J-DSTC） base station cooperation with one bit feedback precoding and power allocation, to remove the significant ICI and ISI experienced by cell boundary users and further improve the system performance and capacity. Simulation results show that the BER performance can be significantly improved by effectively suppressing the ICI and ISI with the proposed scheme. Improved diversity gain and spectrum efficiency can also be achieved,compared to that without cooperation when BSs transmitting in a time-division multiple access manner to avoid ICI for cell edge users,while retains a comparatively low structural and computational complexity.

关 键 词：共信道干扰 不同步干扰 内部联合分布式空时编码 预编码 多蜂窝协同 

分 类 号：TN925[电子电信—通信与信息系统]