Multifrequency Weak Signal Detection Using a Modified Duffing Chaotic System
Hang Geng, Yifan Wang, Kai Chen, Yuhua Cheng, Fan Wu · IEEE Transactions on Instrumentation and Measurement · 2025
The Duffing chaotic system serves as an excellent tool for detecting single frequency weak signals obscured by strong noises, but exhibits poor performance when it comes to the multi-frequency case which is pervasive in numerous engineering applications. By introducing a nonlinear damping term into the original system, this paper establishes an enhanced Duffing chaotic system to surmount this issue whose minimum detectable Signal-to-Noise Ratio (SNR) is largely improved compared with that of the traditional Duffing chaotic system. Based on the Poincar´e map, a quantitative phase state judgment method is proposed to reduce the computational complexity required for phase state determination, and an automatic multi-frequency weak signal detection method is finally formulated by further resorting to a frequency shift module. Experiment results show that this proposed method can detect multi-frequency weak signals with an SNR of -31 dB with the maximum frequency measurement relative error of 0.15%, showing the effectiveness and advantage of the proposed weak detection method.