频分双工协作多点传输系统面向用户的传输模式选择性能

Performance of User-specific Transmission Mode Selection in Frequency Division Duplex Coordinated Multi-point Systems

协作多点传输在提高边缘用户性能方面具有很大的优势,近年来受到了广泛关注。根据基站间交换信息的不同,基站协作的形式可以分为联合处理与波束协调。用户可以根据需要为协作簇内的每个基站选择联合处理、波束协调或不协作的传输方式。本文分析了在基于单小区量化并反馈相位模糊的频分双工系统中,存在信道量化误差时用户端应当如何选择基站传输模式。通过推导用户平均信干噪比的下界并针对特殊位置的用户进行分析,我们发现协作簇内所有基站都参与协作的性能优于不协作的性能,但具体协作方式取决于相位模糊量化是否准确。当相位模糊量化准确时非本地基站都应参与联合处理,否则非本地基站则应进行波束协调。仿真结果表明当用户位于一般的位置时上述结论依然成立。

Coordinated multi-point（CoMP） transmission has draw broad attention due to its advantage of improving the performance of cell-edge users. According to the information exchanged among base stations, the base station cooperative strategies can be roughly divided into joint processing and coordinated beamforming. Each user selects the transmission mode for the base stations in the cooperative cluster, including joint processing, coordinated beamforming and non-CoMP. In this paper we analyze the performance of transmission mode selection at the user in percell codebook based CoMP sys- tems with phase ambiguity feedback. By deriving the lower bound of average SINR and analyze the performance of the users with specific location, we find the performance of base stations participating cooperation is better than that of non-CoMP, and the bits of phase ambiguity determines which cooperative strategy should be selected. When the number of bits is large, all the base stations should participate joint processing, otherwise they will join coordinated beamforming, which is still true for the user with ~eneral location as shown by simulations.