Army Engineering University of PLA, No. 88 Houbiaoying, Qinhuai District, Nanjing 210007, China.
Wuhan Zhong Yuan Electronics Group Company Ltd., Wuhan 430205, China.
Sensors (Basel). 2018 Dec 26;19(1):76. doi: 10.3390/s19010076.
This paper investigates secure communications of energy harvesting untrusted relay networks, where the destination assists jamming signal to prevent the untrusted relay from eavesdropping and to improve the forwarding ability of the energy constrained relay. Firstly, the source and the destination transmit the signals to the relay with maximal ratio transmission (MRT) technique or transmit antenna selection (TAS) technique. Then, the destination utilizes maximal ratio combining (MRC) technique or receive antenna selection (RAS) technique to receive the forwarded information. Therefore, four transmission and reception schemes are considered. For each scheme, the closed-form expressions of the secrecy outage probability (SOP) and the connection outage probability (COP) are derived. Besides, the effective secrecy throughput (EST) metric is analyzed to achieve a good tradeoff between security and reliability. In addition, the asymptotic performance of EST is also considered at the high signal-to-noise ratio (SNR). Finally, simulation results illustrate that: (1) the EST of the system with MRT and MRC scheme are superior to other schemes, however, in the high SNR regime, the EST of the system with MRT scheme is inferior to TAS; and (2) for the source node, there exists an optimal number of antennas to maximize the EST of the proposed schemes.
本文研究了能量收集不可信中继网络的安全通信，其中目的节点协助干扰信号以防止不可信中继窃听，并提高能量受限中继的转发能力。首先，源节点和目的节点使用最大比传输（MRT）技术或发射天线选择（TAS）技术向中继传输信号。然后，目的节点使用最大比合并（MRC）技术或接收天线选择（RAS）技术接收转发信息。因此，考虑了四种传输和接收方案。对于每种方案，推导了保密中断概率（SOP）和连接中断概率（COP）的闭式表达式。此外，还分析了有效保密吞吐量（EST）指标，以在安全性和可靠性之间取得良好的折衷。此外，还在高信噪比（SNR）下考虑了 EST 的渐近性能。最后，仿真结果表明：（1）采用 MRT 和 MRC 方案的系统的 EST 优于其他方案，但在高 SNR 情况下，采用 MRT 方案的系统的 EST 劣于 TAS；（2）对于源节点，存在一个最优的天线数量，可以最大化所提出方案的 EST。
