基于线性弥散空时码的有限反馈干扰对齐算法

干扰对齐(interference alignment,IA)作为极具潜力的干扰管理策略,能获得与用户数量成线性关系的自由度增益,但因其需要全局实时信道状态信息(channel state information,CSI)才能有效实现,使得IA理论向实用的转化将面临众多挑战。针对该问题,本文基于多小区蜂窝系统,提出了一种基于线性弥散空时码的有限反馈干扰对齐算法,该算法将预编码和线性弥散空时码编码进行级联,在只需反馈单个用户CSI的条件下,通过合理地设计预编码矩阵、线性弥散空时码块以及接收端的接收矩阵,来实现干扰的完全消除。仿真结果表明,相比已有研究,新IA算法在实现干扰完全消除的情况下,能够极大地降低系统CSI反馈开销。

Limited feedback interference alignment algorithm based on linear dispersion space-time code

As a potential interference management strategy, interference alignment (IA) can achieve degree of freedom that is linear to the number of users in systems. However, the perfect instantaneous global channel state information (CSI) is required in order to implement IA effectively, which makes the practical usage of IA face many challenges. In terms of this issue, a limited feedback IA algorithm based on linear dispersion space-time code for multi-cell cellular systems is proposed. The main idea of it is to cascade the design of precoding and linear dispersion space-time coding. The interference can be eliminated completely by properly designing precoding matrix, linear dispersion space-time code block and receiving matrix with CSI feedback of only one user. Simulation results verify that the proposed algorithm can not only decrease the feedback overhead significantly, but also eliminate interference completely compared with the existing works.