Composite structure detecting method and system

A composite structure detection system, comprising:

• a terahertz electromagnetic wave generator, configured to generate a terahertz emission electromagnetic wave incident on a composite structure, wherein the composite structure comprises a plurality of interface layers;
• a terahertz electromagnetic wave receiver, configured to detect a plurality of terahertz reception electromagnetic waves reflected, transmitted, or scattered after the terahertz emission electromagnetic wave is incident on the plurality of interface layers of the composite structure;
• and
• a detection device, coupled to the terahertz electromagnetic wave generator and the terahertz electromagnetic wave receiver, configured to measure a plurality of characteristic signals based on the terahertz emission electromagnetic wave and the plurality of terahertz reception electromagnetic waves, and analyze the plurality of characteristic signals to determine a plurality of characteristics of the plurality of interface layers;
• wherein the detection device analyzes the plurality of characteristic signals to determine the plurality of characteristics of the plurality of interface layers by performing a C-Scan planar scan or a B-Scan cross-sectional scan on the composite structure, so as to determine a structural anomaly of one of the plurality of interface layers when the plurality of characteristic signals show a measurement result of signal discontinuity in an interface layer;
• wherein the determination of the structural anomaly of the interface layer is based on a result of the C-Scan planar scan or the B-Scan cross-sectional scan showing that a time-of-flight spectral signal corresponding to the interface layer has a measurement result of signal discontinuity.