Research on extremely low frequency magnetic signal detection and fundamental frequency estimation algorithm

Abstract: The spectrogram of signal is an effective method to analyze the extremely low frequency magnetic field signal. The proposed method is one of the detection algorithm based on the spectrogram. The existence of the target is judged by the harmonics frequency of the spectrum line in the spectrogram. The proposed methods improve the probability of detecting the target and the method can estimate the fundamental frequency of the extremely low frequency magnetic field signal. The simulation and real experiment confirm that the method is effective to analyze the extremely low frequency magnetic field signal.