E ffectively Exploiting Parasitic Arrays for Secret Key Sharing
Abstract: The extraction of a security key from the measurement of the wireless channel can be effectively achieved by means of the use of parasitic antenna arrays; this kind of antenna can be easily implemented in Wi-Fi hotspots or in vehicle-tovehicle communications, providing a securecommunication channel without previous key sharing between the terminals. In this paper, we discuss a methodology to correctly design the parasitic array and a practical method to share a binary key exploiting the virtual channel provided by the parasitic elements. The proposed architecture presents very low complexity, because it requires only one transceiver for each terminal and cheap electronically controllable impedances, making this security technology particularly attractive in low-cost applications.