采用PSK调制的安全传输中人工噪声的优化利用

An Optimized Artificial Noise Strategy in Physical Layer Security Transmission Scheme with PSK Modulation

在采用波束赋形和人工噪声的物理层安全传输系统中,利用人工噪声提高合法接收端的性能.发送端根据发送符号和信道系数判断人工噪声的分量是否对合法接收端的信号检测有益,并由此将人工噪声分为有益噪声和普通噪声,分别进行不同的波束赋形处理.在不改变人工噪声干扰窃听端接收的前提下,利用人工噪声提高合法接收端的接收性能.对采用相移键控(PSK)调制时的误码性能和保密容量进行理论分析和仿真,结果显示,与传统的人工噪声方案相比,所提出的人工噪声方案可提高合法接收端的性能,改善保密容量.

A strategy was studied which takes the advantage of artificial noise to improve the performance of legitimate user for physical layer security transmission systems using beamforming technology and artificial noise.Based on transmitted symbols and channel coefficients,the transmitter determines whether or not part of artificial noises are beneficial to the signal detection at the legitimate receiver.It divides the original artificial noises into two parts： constructive noises and common noises,then it designs beamforming vectors accordingly.By exploiting the constructive noises,the signal-to-noise ratio at the legitimate receiver is improved while that at the illegal receiver will remain the same.The bit error rate and the secrecy capacity are analyzed and simulated when phase shift keying modulation is used.It is demonstrated that the proposed scheme can improve the performance of the legal receiver and enhance secrecy capacity.