本文考虑了一个利用full-duplex simultaneous wireless information and power transfer (FDSWIPT)双向中继提供移动通信蜂窝网络中小区覆盖,同时改进吞吐量和能量效率的应用场景.针对FD-SWIPT双向中继研究存在问题,提出了FD-SWIPT双向中继系统中基于天线选择与波束成形联合优化的高能效和吞吐量最大化方案.首先,给出了一种低复杂度次优天线分组算法,在中继接收端使用天线分组策略,将信道条件好的接收信号用于传输,剩下的信号用于能量采集.进一步,在中继发送端设计了波束成形方案,并利用最大广义特征值方法优化波束成形矢量,达到优化接收端信干噪比的目的.仿真结果表明,所提出的联合优化方案能有效提升系统的和吞吐量与能量效率,且天线选择方案起到了重要的作用.
This paper presents noncooperative and cooperative security transmission schemes for multiple-input multiple-output(MIMO) Gaussian wiretap channel with one helper for antenna configuration with arbitrary number. In these two schemes, the transmitter performs beamforming based on generalized singular value decomposition(GSVD), where an appropriate power allocation algorithm is utilized. Meanwhile, the helper sends artificial noise for higher secrecy rate. However, the transmission strategies for the artificial noise are different in the two schemes. In the first scheme, the helper adopts GSVD-based beamforming. Nevertheless, in this scheme, the impact of the artificial noise on the information signal at the receiver is not considered. To solve the problem, the helper performs space projection(SP)-based beamforming in the second scheme. In this scheme, suboptimal weighting factors are introduced to reduce the computational complexity, which can be adapted to the change of the channel quality. Theoretical analysis for the performance of the two proposed schemes is then given. Furthermore, simulation results indicate that the two presented schemes perform better than the existed schemes without helper. They also show that in the second scheme the suboptimal parameter setting is better than equal parameter setting and quite close to optimal parameter setting.