多天线中继协作系统中的中继干扰抑制与分析

The traditional half-duplex relay protocols, which usually send signals using time division multiple access in order to ensure orthogonality between the transmitting nodes and to avoid the requirements of full-duplex, have brought the loss of spectral efficiency. In order to reduce the loss, two-path relay and full-duplex relay protocols have been widespread concern in the domestic and foreign scholars. However their performance is subject to the impact of relay interference, including inter-relay interference for two-path relaying and self-interference for full-duplex relaying. The project intends to research relay interference suppression and analysis for cooperative systems based on multi-antenna relays. As to two-path relaying, inter-relay interference analysis model will be established when multi-antenna relays are employed, and interference alignment technique will be used to eliminate the interference; As to full-duplex relaying, the system model and self-interference model will be established firstly, and then the impact of interference on system performance and relay selection with self-interference will be investigated furtherly, and finally joint precoding and traditional time-domain filter will be employed to effectively suppress the self-interference and to improve the spectral efficiency of the system. Through the project, we will analyze and solve interference suppression of wireless cooperative communication in order to achieve high-speed and reliable transmission of data, and provide technical reserves and theoretical support for the practical application of the relay cooperative system.

传统的半双工中继协议通常采用时分多址方式发送信号以保证发射节点间的正交性并避免了中继节点的全双工要求，却带来了频谱效率的损失。为了减少该损失，两路中继和全双工中继协作方案得到国内外学者们的广泛关注，然而他们的性能受制于中继干扰的影响，包括两路中继系统的中继间干扰和全双工中继系统的中继自干扰。本项目拟研究基于多天线中继的协作系统的中继干扰抑制与分析。针对两路中继，配置多天线中继，建立中继间干扰分析模型，采用干扰对准技术消除中继间干扰；针对全双工中继，建立系统模型和全双工中继自干扰模型，深入研究中继自干扰对系统性能的影响和考虑自干扰的中继选择，采用联合预编码技术和传统的时域滤波器用于有效抑制全双工中继自干扰，提高系统的频谱利用率。通过本项目，分析和解决无线协作通信的干扰抑制问题，从而实现数据的高速可靠传输，为中继协作传输系统的实际应用提供技术储备和理论支撑。

针对传统的半双工中继协议为保证发射节点间的正交性而产生的频谱效率损失，本项目重点研究两路中继和全双工中继协作系统。首先，项目组建立了这两种中继协作系统的系统模型，深入研究发现他们的性能受制于中继干扰的影响，包括两路中继系统的中继间干扰和全双工中继系统的中继自干扰。接着，针对两路中继，配置多天线中继，建立中继间干扰分析模型，课题组对这一干扰进行了数学建模及理论推导，深入分析这一干扰对两路中继协作系统性能的损害，引入发送和接收波束成形技术，通过对收发波束成形变量的优化，设计出最优波束成形矢量，仿真结果表明该方案有效地抑制了中继间干扰信号，提高了系统的信道容量。最后，针对全双工中继，建立系统模型和全双工中继自干扰模型，深入研究中继自干扰对系统性能的影响和考虑自干扰的中继选择，并提出了两种干扰抑制算法用于有效抑制全双工中继自干扰，提高了系统的频谱利用率。本项目通过分析和解决无线协作通信的干扰抑制问题，从而实现数据的高速可靠传输，为中继协作系统的实际应用提供技术支撑。