研究了由1个单天线的源节点、目的节点、窃听节点和1个多天线的中继节点组成的系统中,通过能量协作增强保密传输性能的问题.为提高保密速率,中继节点发送经过波束赋形的干扰信号来干扰窃听者.在中继能量供应受限的情况下,提出一种协作干扰与能量协作相结合的方案.源端在能量约束范围内采用能量转移的方式为中继提供用于发送干扰信号的能量.对能量转移量、能量转移时间和干扰信号波束赋形的优化问题进行了求解.仿真结果表明,在不消耗中继自身能量的条件下,与直接传输相比,能量协作和协作干扰方案能够显著提高系统的保密性能.
It attempts to solve the problem of enhancing physical-layer transmission security based on energy cooperation in the system which consists of one single-antenna source,destination,eavesdropper and one multi-antenna relay. To improve the secrecy rate,the multi-antenna relay transmits beamformed jamming signals to disturb the eavesdropper. A scheme of cooperative jamming with energy cooperation is proposed for the scenario when the energy supply of the relay is limited. Within the scope of the energy constraint,the source provides energy for the relay to transmit jamming signals. The optimal solution is derived for the amount of energy needed to transfer,transferring time and the beamforming vector of the jamming signals. The simulation results show that in the case when no energy of the relay is consumed,the scheme of energy cooperation and jamming can significantly improve the secrecy rate compared with direct transmission.