Joint Enhancement of Transducer Design and Time–Frequency Analysis for Artifact-Resilient Guided-Wave Testing

This paper presents an artifact-suppressed guided-wave time–frequency domain reflectometry for comprehensive pipeline inspection. A novel 3D-printed piezoelectric transducer module (3DP-PTM) is developed to enhance mechanical stability, electromagnetic isolation, and signal fidelity. The 3DP-PTM is experimentally validated on a stainless-steel pipe with a simulated transverse notch, showing significant improvements in signal-to-noise ratio, envelope preservation index, and signal-to-ringing ratio over conventional flexible printed circuit-based systems. The 3DP-PTM hardware and an advanced time-frequency analysis are co-designed as an integrated guided-wave testing. To enable reliable assessment of artifact-suppression capability within the co-designed system, a new composite metric, cSDR, which quantitatively evaluates both peak preservation and artifact reduction is proposed. The proposed advanced time-frequency analysis demonstrates superior detection sensitivity and monotonic correlation with defect depth in extended tests using carbon-steel pipes. The combined system enables robust, high-resolution pipeline diagnostics under varying structural conditions.