基于存储示波器的PS/2键盘电磁截获研究

基于存储示波器的PS2键盘电磁截获研究

内容简介：计算机键盘有用信号电磁截获的传统方法是基于宽带接收机完成的，这种方法较复杂且需要较多的设备和空间。为使键盘截获技术向小型化和实用化过渡，提出了使用基于软件无线电的解码技术及基于存储示波器全频谱远场截获。首先，基于频谱对比的方法对有用信号的频段进行初判，然后对截获的全频域信号中包含有敏感信息的频段基于软件无线电的方法进行带通滤波和解调。最后，使用一种能够精确判别按键信息的解码方法，通过预先设计的程序来实现信息的截获。实验结果表明计算机键盘有用信号电磁截获实现实用化和小型化是有一定可行性的，并且能够得到比较精确的结果。

Abstract：The general technique based on a wide-band receiver may be complicated and need more devices. To make this technique for miniaturization and practicability, a new decoding technique based on software defined radio and full-spectrum far-field interception based on storage oscilloscope is represented. In advance, an interesting frequency is discovered by spectral analyzers. A full spectrum signal acquired by storage oscilloscope is filtered and demodulated using software radio technology on our interesting frequency. This paper introduces an accurate method to completely recover the keystrokes, and then get the result using pre-design software. Experimental results show that the miniaturization and practicality of PS/2 keyboard electromagnetic interceptions are feasible, and the result is also precise.

作者：周一帆, 吕英华, 杜玉雷,

关键词：PS/2键盘, 电磁泄漏发射, 软件无线电, TEMPEST