An iterative frequency-domain envelope-tracking filter for dispersive signal decomposition in structural health monitoring. (1st November 2022)

• Record Type: Journal Article
• Authors: Jiang, Yuan; Niu, Gang
• Is Part Of: Mechanical systems and signal processing. Volume 179(2022)
• Publication Date: 2022-11-01
• Subjects: Dispersive signal decomposition -- Group delay -- Broadband Lamb wave -- Iterative frequency-domain envelope-tracking filter -- Structural health monitoring; ACMP Adaptive chirp mode pursuit -- DCM Dispersion compensation method -- DFRE Dual fast ridge extraction -- EMD Empirical mode decomposition -- FICD Frequency-domain intrinsic component decomposition -- GD Group delay -- GDC Generalized dispersive component -- GDMD Generalized dispersive mode decomposition -- IA Instantaneous amplitude -- IETF Iterative envelope-tracking filter -- IF Instantaneous frequency -- IFETF Iterative frequency-domain envelope-tracking filter -- MSE Mean square error -- RE Relative error -- RPRG Ridge path regrouping -- SFFT Short-frequency Fourier transform -- SNR Signal-to-noise ratio -- SST Synchrosqueezing transform -- STFT Short-time Fourier transform -- TBW Time bandwidth -- TF Time-frequency -- TFA Time-frequency analysis -- TFR Time-frequency representation; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2022.109329
• Languages: English
• ISSNs: 0888-3270

Abstract

Highlights: A novel dispersive decomposition method named iterative frequency-domain envelope-tracking filter (IFETF) for structural health monitoring. Frequency envelope tracking with joint-estimation technique to accurately extract the overlapped dispersive components. Non-parameterized group delay (GD) refinement procedure to ameliorate the time–frequency resolution. Adaptive ridge detection technique to automatically estimate the number of components and their GDs with less prior knowledge. Comprehensive comparison among five related time–frequency analysis methods. Abstract: Dispersive signals are omnipresent in structural health monitoring and nondestructive testing. Due to the strong dispersion and multimodal characteristics, such signals often contain multiple components with frequency-varying group delays (GDs) overlapping in time–frequency (TF) domain, bringing great challenges to the existing signal processing methods. This paper presents a novel dispersive signal decomposition method named iterative frequency-domain envelope-tracking filter (IFETF) to accurately estimate the dispersion curves and separate overlapped components. Specifically, an envelope tracking issue is introduced in frequency domain based on dispersive signal model. Then, GDs are refined by recovered frequency envelope, and an iterative processing procedure is designed to ameliorate the TF resolution. To initialize the IFETF, an adaptive ridge detection technique is introduced to automatically estimate the number of components and their GDs with little prior knowledge. In addition, a high-quality TF representation can be constructed according to the results of IFETF, unambiguously revealing TF patterns of a multi-component dispersive signal. The proposed method was demonstrated by numerical analysis and engineering applications on broadband Lamb wave inspection and rail damage detection. Compared with traditional TF analysis techniques, the results show that the IFETF provides higher accuracy and efficiency in signal reconstruction and GD estimation.