中文摘要：

终端直通（D2D）用户在复用蜂窝网络频谱资源提高频谱效率的同时，不可避免地会受到蜂窝用户的干扰，为此该文提出一种基于复数域网络编码的D2D传输方案。D2D用户复用蜂窝下行链路频谱，将蜂窝基站和D2D发送端作为两个独立的信源，蜂窝用户作为中继节点。蜂窝用户对检测到的蜂窝信号和D2D信号进行复数域网络编码，D2D接收端采用最大似然多用户检测恢复出D2D信号，消除蜂窝用户对D2D用户的信号干扰。理论分析与仿真结果表明，该方案较传统的D2D4传输案，在确保消除蜂窝信号干扰的同时，能显著提高系统可达速率，降低符号错误概率。

英文摘要：

Terminal users of device-to-device （D2D） communication inevitably will be interfered by cellular users while using multiplexing cellular network spectrum to improve spectrum efficiency. A D2D transmission scheme based on complex field network coding is proposed in this paper. Specifically, as the D2D user multiplexes cellular downlink spectrum, the cellular base station and D2D sender can be regarded as two independent sources, and meanwhile the cellular user as relay node. Moreover, the cellular user encodes the detected cellular signals and D2D signals by complex field network coding, and the D2D receiver can recover D2D signals by adopting maximum likelihood multiuser detection to eliminate cellular signal interference. Theoretical analysis and simulation results show that, compared with traditional D2D transmission schemes, the proposed scheme can improve system achievable rate evidently and reduce symbol error probability, simultaneously ensuring the elimination of cellular signal interference.