An SEI-Based Identification Scheme for Illegal FM Broadcast

Illegal radio signals do harm to social security and electromagnetic safety with low cost and huge economic benefits. Therefore, illegal radio signal monitoring is an important part of electromagnetic safety monitoring. In this paper, we propose an identification method, characterized by radio frequency (RF) fingerprint, for illegal frequency modulation (FM) broadcast. The idea of specific emitter identification (SEI) is introduced in broadcast monitoring. Illegal FM radio station is considered as the unique emitter individual which is different from the legal radio stations. The individual features are extracted as RF fingerprints of the FM radio stations including fractal features and refined composite multiscale dispersion entropy (RCMDE). Illegal FM broadcasting signals can be identified and detected based on local outliers factor (LOF) algorithm. Experimental results show that the SEI-based method can effectively detect illegal FM broadcasting signals. It is capable of achieving nearly 99% accuracy in legal and illegal FM radio station identification tasks.