双向全双工中继系统自干扰抑制

摘要

As a key technology of 5G,Full-Duplex Relay (FDR) technology with its advantages of frequency reuse is concerned by the industry. FDR not only can improve the system capacity but also be used at very low cost to expand coverage. However,the characteristics of simultaneously sending and receiving signals of the same frequency result in serious self-interference of loop,which is a major factor restricting the development. For the core issue,Self-Interference Cancellation (SIC),in FDR system,the method of special domain is used to eliminate interference in MIMO in order to reduce the bit error rate and improve the system capacity. FDR is combined with bidi-rectional communication to establish bidirectional full-duplex relay system model. The encoder and decoder of relay nodes is designed based on original zero space projection,and time-domain method is applied to eliminate interference from the source node receiving end. Theoretical analysis and simulation results show that this model can effectively eliminate the bidirectional FDR system self-interference, greatly improving system performance.%作为5G的关键技术,全双工中继(Full-Duplex Relay,FDR)技术凭借其频率复用的优势而备受业界关注。 FDR不仅能够提高系统容量,还可以用极低的成本来扩大覆盖范围。然而,其同时同频收发信号的特性导致严重的环路自干扰,这成为制约其发展的主要因素。针对FDR系统自干扰抑制( Self-Interference Cancellation,SIC)这一核心问题,主要采用空域方法抑制MIMO中继自干扰,以降低系统误码率,提高系统容量。将FDR与双向通信相结合,建立双向全双工中继系统模型。基于原零空间投影法设计中继节点的编译码器,并采用时域方法抑制源节点接收端的自干扰。理论分析和仿真结果表明,采用这样的设计模型能够有效抑制双向FDR系统自干扰,大大提升系统性能。