Wireless Physical-layer Security Using Precoding and an Active Eavesdropper

The wireless physical layer security can assist traditional encryption mechanisms by generating the keys, for instance. However, some techniques allow hiding information directly in the physical layer, such as performing precoding at the legitimate user information about the channel, such as the received signal strength or the phase response. Most works on this kind of precoding also considers a passive eavesdropper. This work considers an active eavesdropper and proposes the use of a precoder based of the full channel impulse response. The results show the effectiveness of the proposed technique to secure the information transmission.