Local Frechet Distance In Specific Emitter Identification

Specific Emitter Identification (SEI) is one of most difficult tasks in modern electronic warfare. The principle function of the SEI is utilizing fingerprint features to identify different emitters of the same type by a precise measurement, which plays an important role in the recognition process. Under the premise that the time-domain waveforms such as the instantaneous amplitude and frequency are specified as the fingerprint features, the frechet distance can achieve preferable identification accuracy, compared to the Hausdorff and Dynamic Time Warping (DTW) distance. Unfortunately, due to the disadvantage of its high time complexity, the frechet distance is unable to satisfy the requirement of real-time data processing in practical application, especially in the military field. Combining waveform structures of these fingerprint features, a local frechet distance is proposed in the paper. The new algorithm can provide a lower time complexity and hardly impact the identification accuracy.