Wireless device identification using oscillator control voltage as RF fingerprint

Device identification has been considered as a main trend to maintain security in wireless communications. Specific characteristics of different components of transmitters have been recently exploited as their RF fingerprints. In this paper, a new method is presented to uniquely identify a transmitter using a phase locking mechanism. In the proposed method, a Phase-Locked Loop is used to lock on the transmitter to observe the control voltage of the oscillator. The steady state value of the control voltage is used as fingerprint to identify a transmitter.