Specific emitter identification based on horizontal visibility graph

Specific emitter identification (SEI) techniques are often used in civilian and military spectrum-management operations and they are helpful to enhance the security of wireless network. In this letter, we investigate SEI problem by using features generated by the nonlinearity contained in received signals. First, the horizontal visibility graph (HVG) method is applied to the instantaneous amplitude, phase and frequency of received signals to derive their degree distributions. Then, a feature vector formed by the normalized Shannon Entropy (NSE) and the Fisher Information measure (FIM) obtained from these degree distributions are used as RF fingerprints. Finally, four emitters produced by a certain manufacturer are utilized to evaluate the performance of the proposed method. For comparison purpose, the method based on the normalized permutation entropy (NPE) is used as a gold standard. Experimental results show that the proposed method is quite effective and its performance is better than that of the NPE-based method in the case of small amount of data. Moreover, the proposed method does not need to distinguish between transient signals and steady-state signals and there is no parameter to be determined before performing the SEI system, which makes the proposed method relatively practical.