信息电磁泄漏侦收系统抗噪声性能研究

On the anti-noise performance of eavesdropper on information electromagnetic leakage

信息电磁泄漏侦收系统的抗噪声性能直接关系到系统整体性能。根据CRT显示器信息电磁泄漏机理及侦收系统工作原理,建立了信息电磁泄漏与侦收的数字信号基带传输模型,分别讨论了有、无码间干扰时侦收误码率与侦收距离、叠加次数、噪声功率的关系,利用Q函数描述了误码率的变化趋势。用所研制的侦收系统进行了实验,实验结果与理论分析一致性良好。

The anti-noise performance of eavesdropper on information electromagnetic leakage, which directly affects general performance of the eavesdropper, is analyzed. The model of digital base band transmission is constructed according to the mechanism of information electromagnetic leakage from cathode-ray-tube （CRT） displays and the working principle of the eavesdropper. The relationship between bit error rates and intercept distance, superposition times, noise power is discussed under the circumstances of ISI and ISI-free. The varying trend of bit error rates, which is subject to above parameters, is described with Q function. Good agreement is got between experimental results and theoretical analysis.