在基于正交频分多址接入(OFDMA)技术的蜂窝移动小区中,小区间的干扰是影响系统性能的主要因素。多点协调(CoMP)技术被视为能够协调小区间干扰的主要手段。在下行多点协作传输系统中,小区基站采用三向天线来对小区划分扇区,从而消除了相邻小区边缘处的干扰。各扇区分别计算扇区内用户的大尺度信干比(SIR),小区之间通过共享大尺度信干比信息,对各自服务的用户按照一定的规则进行匹配,对小区中心用户的SIR和边缘用户的SIR进行了折中,从而有效解决小区边缘用户由于小区间干扰带来的低信干噪比(SINR)问题。仿真结果表明,本文提出的用户匹配算法以较小的反馈开销,较大地提高了小区边缘用户的信干噪比和系统吞吐量。
In the Orthogonal Frequency Division Multiple Access (OFDMA) cellular mobile communication systems, Inter-cell interference (ICI) become the main factor in affecting system performance. Coordinated Multipoint (CoMP) is one of the key technologies in dealing with the interference coordination. In downlink coordinated multi-point transmission sys- tems, base-stations (BS) adopt tri-sector antenna divide the cell into three fan sectors so that the interference between the neighborhood cellulars can be greatly dispelled. Base-stations computes the large scale Signal to Interference Ratio(SIR) for the served users, and cell match its users with ones in the other cells according to certain rules by sharing the large scale SIR information. It realizes a trade-off of SIR between the users in the center of the cellular and users on the edge of the cel- lular, in order to solve the low Signal to Interference plus Noise Ratio (SINR) problem which due to the ICI at cell edge. Simulation results show that the proposed algorithm significantly improves cell edge SINR and throughput with less feedback overhead.