Specific Emitter Identification Based on Nonlinear Dynamical Characteristics

Specific emitter identification (SEI) designates the unique transmitter of a given signal, using only external feature measurements called the RF fingerprints of the signal. SEI is often used in military and civilian spectrum-management operations. The SEI technique has also been applied to enhance the security of wireless network, such as VHF radio networks, Wi-Fi networks, cognitive radios, and cellular networks. A novel SEI method based on nonlinear dynamical characteristics is proposed in this paper. The method works based on the actual signal's inherent nonlinear dynamical characteristics. The permutation entropy is extracted as the signal's RF fingerprint to identify the unique transmitter. The quadrature phase-shift keying (QPSK) signals from four wireless network cards and differential quadrature phase-shift keying (DQPSK) signals from three digital radios are utilized to evaluate the performance of the method. Experimental results demonstrate that the proposed method is effective. On the other hand, the proposed method is convenient to implement in a PC.