Intrusion detection for wireless power networks, near-field communication, and side-channel attacks

Near-field approximations to Maxwell´s equations reveal an interesting property of inductively-coupled links that are so frequently used in wireless power transfer: observation disturbs the system. We propose theoretical strategies and include preliminary practical implementations that demonstrate how this property can be used to detect presence of an adversary/intruder/eavesdropper, and thereby secure (a) wireless power transfer from power-stealing; (b) near-field information transfer; and (c) circuits from hardware probing attacks. These strategies rely on detecting the distortions in the electro-magnetic field induced by the presence of an extraneous element. We implement two of such circuits and compare them on their stability to detect such eavesdroppers.