基于携能通信的非信任双向中继网络安全传输方案

Security Transmission Scheme for Two-way Untrusted Relay Networks Based on Simultaneous Wireless Information and Power Transfer

针对非信任双向中继网络的能量受限和信息安全问题,该文提出一种基于无线携能通信(SWIPT)与人工噪声辅助的物理层安全传输方案。该方案中的非信任中继采用功率分割(PS)策略辅助合法用户进行保密通信,而全双工干扰机在进行能量采集的同时发送人工噪声以确保系统安全。以最大化系统保密性能为目标,优化了中继的PS因子,推导了保密和速率的解析式及高信噪比条件下最佳PS因子的闭式解。特别针对非理想信道状态信息的情况,分析了信道估计误差对系统保密性能的影响。仿真结果验证了理论推导的正确性,并证明了所提的基于PS策略的干扰机协同传输方案相比采用时间切换(TS)策略或目的节点协同干扰的方案具有更优的保密性能。

The physical-layer security transmission scheme based on Simultaneous Wireless Information and Power Transfer(SWIPT)and artificial noise-aided is proposed to solve the energy-constrained and information security issues upon the two-way untrusted relay networks.The Power Splitting(PS)strategy is adopted by the untrusted relay to assist the confidential communication,where a full-duplex jammer is assigned to send the artificial noise while harvesting energy,to ensure the system security.The PS factor is optimized to maximize the secrecy performance,and then the closed-form expressions of the secrecy sum-rate and optimal PS ratio are derived in the high signal-to-noise ratio regime.Besides,the impacts of the channel estimation error on the system security are analyzed for the imperfect channel state information.Simulation results validate the correctness of the theoretical derivation and demonstrate that the proposed transmission scheme based on PS strategy and friendly jammer outperforms that based on the Time Switching(TS)strategy or destination-aided jamming.